diff --git a/build/integration/collaboration_features/autocomplete.feature b/build/integration/collaboration_features/autocomplete.feature
index 5044758a70f..763b95bf170 100644
--- a/build/integration/collaboration_features/autocomplete.feature
+++ b/build/integration/collaboration_features/autocomplete.feature
@@ -41,28 +41,88 @@ Feature: autocomplete
     Then get autocomplete for "autocomplete"
       | id | source |
 
+  Scenario: getting autocomplete from address book with enumeration
+    Given As an "admin"
+    And sending "PUT" to "/cloud/users/autocomplete" with
+      | key | email |
+      | value | autocomplete@example.com |
+    And there is a contact in an addressbook
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get autocomplete for "auto"
+      | id | source |
+      | auto | users |
+      | autocomplete | users |
+      | autocomplete2 | users |
+    Then get autocomplete for "example"
+      | id | source |
+      | autocomplete | users |
+    Then get autocomplete for "autocomplete@example.com"
+      | id | source |
+      | autocomplete | users |
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "yes"
+    Then get autocomplete for "auto"
+      | id | source |
+      | auto | users |
+      | autocomplete | users |
+      | autocomplete2 | users |
+    Then get autocomplete for "example"
+      | id | source |
+      | autocomplete | users |
+    Then get autocomplete for "autocomplete@example.com"
+      | id | source |
+      | autocomplete | users |
+      | autocomplete | users |
+
+  Scenario: getting autocomplete from address book without enumeration
+    Given As an "admin"
+    And sending "PUT" to "/cloud/users/autocomplete" with
+      | key | email |
+      | value | autocomplete@example.com |
+    And there is a contact in an addressbook
+    And parameter "shareapi_allow_share_dialog_user_enumeration" of app "core" is set to "no"
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get autocomplete for "auto"
+      | id | source |
+    Then get autocomplete for "example"
+      | id | source |
+    Then get autocomplete for "autocomplete@example.com"
+      | id | source |
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "yes"
+    Then get autocomplete for "auto"
+      | id | source |
+      | auto | users |
+    Then get autocomplete for "example"
+      | id | source |
+    Then get autocomplete for "autocomplete@example.com"
+      | id | source |
+      | autocomplete | users |
+      | autocomplete | users |
+
   Scenario: getting autocomplete emails from address book with enumeration
     Given As an "admin"
     And sending "PUT" to "/cloud/users/autocomplete" with
       | key | email |
       | value | autocomplete@example.com |
     And there is a contact in an addressbook
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get email autocomplete for "auto"
+      | id | source |
     Then get email autocomplete for "example"
       | id | source |
-      | autocomplete | users |
       | leon@example.com | emails |
       | user@example.com | emails |
+    Then get email autocomplete for "autocomplete@example.com"
+      | id | source |
+      | autocomplete@example.com | emails |
+    When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "yes"
     Then get email autocomplete for "auto"
       | id | source |
-      | autocomplete | users |
     Then get email autocomplete for "example"
       | id | source |
-      | autocomplete | users |
       | leon@example.com | emails |
       | user@example.com | emails |
     Then get email autocomplete for "autocomplete@example.com"
       | id | source |
-      | autocomplete | users |
 
   Scenario: getting autocomplete emails from address book without enumeration
     Given As an "admin"
@@ -72,10 +132,15 @@ Feature: autocomplete
     And there is a contact in an addressbook
     And parameter "shareapi_allow_share_dialog_user_enumeration" of app "core" is set to "no"
     When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "no"
+    Then get email autocomplete for "auto"
+      | id | source |
     Then get email autocomplete for "example"
       | id | source |
       | leon@example.com | emails |
       | user@example.com | emails |
+    Then get email autocomplete for "autocomplete@example.com"
+      | id | source |
+      | autocomplete@example.com | emails |
     When parameter "shareapi_restrict_user_enumeration_full_match" of app "core" is set to "yes"
     Then get email autocomplete for "auto"
       | id | source |
@@ -85,7 +150,6 @@ Feature: autocomplete
       | user@example.com | emails |
     Then get email autocomplete for "autocomplete@example.com"
       | id | source |
-      | autocomplete | users |
 
   Scenario: getting autocomplete with limited enumeration by group
     Given As an "admin"
diff --git a/build/integration/features/bootstrap/Provisioning.php b/build/integration/features/bootstrap/Provisioning.php
index 935ad2a4a1d..16fb9e297c7 100644
--- a/build/integration/features/bootstrap/Provisioning.php
+++ b/build/integration/features/bootstrap/Provisioning.php
@@ -16,6 +16,12 @@ require __DIR__ . '/../../vendor/autoload.php';
 trait Provisioning {
 	use BasicStructure;
 
+	/** @var array */
+	private $appsToEnableAfterScenario = [];
+
+	/** @var array */
+	private $appsToDisableAfterScenario = [];
+
 	/** @var array */
 	private $createdUsers = [];
 
@@ -28,6 +34,19 @@ trait Provisioning {
 	/** @var array */
 	private $createdGroups = [];
 
+	/** @AfterScenario */
+	public function restoreAppsEnabledStateAfterScenario() {
+		$this->asAn('admin');
+
+		foreach ($this->appsToEnableAfterScenario as $app) {
+			$this->sendingTo('POST', '/cloud/apps/' . $app);
+		}
+
+		foreach ($this->appsToDisableAfterScenario as $app) {
+			$this->sendingTo('DELETE', '/cloud/apps/' . $app);
+		}
+	}
+
 	/**
 	 * @Given /^user "([^"]*)" exists$/
 	 * @param string $user
@@ -803,13 +822,23 @@ trait Provisioning {
 		return $extractedElementsArray;
 	}
 
-
 	/**
-	 * @Given /^app "([^"]*)" is disabled$/
+	 * @Given /^app "([^"]*)" enabled state will be restored once the scenario finishes$/
 	 * @param string $app
 	 */
-	public function appIsDisabled($app) {
-		$fullUrl = $this->baseUrl . 'v2.php/cloud/apps?filter=disabled';
+	public function appEnabledStateWillBeRestoredOnceTheScenarioFinishes($app) {
+		if (in_array($app, $this->getAppsWithFilter('enabled'))) {
+			$this->appsToEnableAfterScenario[] = $app;
+		} elseif (in_array($app, $this->getAppsWithFilter('disabled'))) {
+			$this->appsToDisableAfterScenario[] = $app;
+		}
+
+		// Apps that were not installed before the scenario will not be
+		// disabled nor uninstalled after the scenario.
+	}
+
+	private function getAppsWithFilter($filter) {
+		$fullUrl = $this->baseUrl . 'v2.php/cloud/apps?filter=' . $filter;
 		$client = new Client();
 		$options = [];
 		if ($this->currentUser === 'admin') {
@@ -820,7 +849,15 @@ trait Provisioning {
 		];
 
 		$this->response = $client->get($fullUrl, $options);
-		$respondedArray = $this->getArrayOfAppsResponded($this->response);
+		return $this->getArrayOfAppsResponded($this->response);
+	}
+
+	/**
+	 * @Given /^app "([^"]*)" is disabled$/
+	 * @param string $app
+	 */
+	public function appIsDisabled($app) {
+		$respondedArray = $this->getAppsWithFilter('disabled');
 		Assert::assertContains($app, $respondedArray);
 		Assert::assertEquals(200, $this->response->getStatusCode());
 	}
@@ -830,18 +867,7 @@ trait Provisioning {
 	 * @param string $app
 	 */
 	public function appIsEnabled($app) {
-		$fullUrl = $this->baseUrl . 'v2.php/cloud/apps?filter=enabled';
-		$client = new Client();
-		$options = [];
-		if ($this->currentUser === 'admin') {
-			$options['auth'] = $this->adminUser;
-		}
-		$options['headers'] = [
-			'OCS-APIREQUEST' => 'true',
-		];
-
-		$this->response = $client->get($fullUrl, $options);
-		$respondedArray = $this->getArrayOfAppsResponded($this->response);
+		$respondedArray = $this->getAppsWithFilter('enabled');
 		Assert::assertContains($app, $respondedArray);
 		Assert::assertEquals(200, $this->response->getStatusCode());
 	}
@@ -854,18 +880,7 @@ trait Provisioning {
 	 * @param string $app
 	 */
 	public function appIsNotEnabled($app) {
-		$fullUrl = $this->baseUrl . 'v2.php/cloud/apps?filter=enabled';
-		$client = new Client();
-		$options = [];
-		if ($this->currentUser === 'admin') {
-			$options['auth'] = $this->adminUser;
-		}
-		$options['headers'] = [
-			'OCS-APIREQUEST' => 'true',
-		];
-
-		$this->response = $client->get($fullUrl, $options);
-		$respondedArray = $this->getArrayOfAppsResponded($this->response);
+		$respondedArray = $this->getAppsWithFilter('enabled');
 		Assert::assertNotContains($app, $respondedArray);
 		Assert::assertEquals(200, $this->response->getStatusCode());
 	}
diff --git a/build/integration/features/bootstrap/Sharing.php b/build/integration/features/bootstrap/Sharing.php
index 0cc490ff110..d93f114f27b 100644
--- a/build/integration/features/bootstrap/Sharing.php
+++ b/build/integration/features/bootstrap/Sharing.php
@@ -697,7 +697,13 @@ trait Sharing {
 		if ($body instanceof TableNode) {
 			$parameters = [];
 			foreach ($body->getRowsHash() as $key => $value) {
-				$parameters[] = $key . '=' . $value;
+				if ($key === 'shareTypes') {
+					foreach (explode(' ', $value) as $shareType) {
+						$parameters[] = 'shareType[]=' . $shareType;
+					}
+				} else {
+					$parameters[] = $key . '=' . $value;
+				}
 			}
 			if (!empty($parameters)) {
 				$url .= '?' . implode('&', $parameters);
@@ -732,9 +738,46 @@ trait Sharing {
 			$shareeType = substr($shareeType, 6);
 		}
 
+		// "simplexml_load_string" creates a SimpleXMLElement object for each
+		// XML element with child elements. In turn, each child is indexed by
+		// its tag in the SimpleXMLElement object. However, when there are
+		// several child XML elements with the same tag, an array with all the
+		// children with the same tag is indexed instead. Therefore, when the
+		// XML contains
+		// <XXX>
+		//   <element>
+		//     <label>...</label>
+		//     <value>...</value>
+		//   </element>
+		// </XXX>
+		// the "$elements[$shareeType]" variable contains an "element" key which
+		// in turn contains "label" and "value" keys, but when the XML contains
+		// <XXX>
+		//   <element>
+		//     <label>...</label>
+		//     <value>...</value>
+		//   </element>
+		//   <element>
+		//     <label>...</label>
+		//     <value>...</value>
+		//   </element>
+		// </XXX>
+		// the "$elements[$shareeType]" variable contains an "element" key which
+		// in turn contains "0" and "1" keys, and in turn each one contains
+		// "label" and "value" keys.
+		if (array_key_exists('element', $elements[$shareeType]) && is_int(array_keys($elements[$shareeType]['element'])[0])) {
+			$elements[$shareeType] = $elements[$shareeType]['element'];
+		}
+
 		$sharees = [];
 		foreach ($elements[$shareeType] as $element) {
-			$sharees[] = [$element['label'], $element['value']['shareType'], $element['value']['shareWith']];
+			$sharee = [$element['label'], $element['value']['shareType'], $element['value']['shareWith']];
+
+			if (array_key_exists('shareWithDisplayNameUnique', $element)) {
+				$sharee[] = $element['shareWithDisplayNameUnique'];
+			}
+
+			$sharees[] = $sharee;
 		}
 		return $sharees;
 	}
diff --git a/build/integration/openldap_features/openldap-uid-username.feature b/build/integration/openldap_features/openldap-uid-username.feature
index bee4098972b..02336b05128 100644
--- a/build/integration/openldap_features/openldap-uid-username.feature
+++ b/build/integration/openldap_features/openldap-uid-username.feature
@@ -161,5 +161,5 @@ Feature: LDAP
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Elisa | 0 | elisa |
+      | Elisa | 0 | elisa | elisa@nextcloud.ci |
     And "exact groups" sharees returned is empty
diff --git a/build/integration/sharees_features/sharees.feature b/build/integration/sharees_features/sharees.feature
index 9480ef997ae..4ff6d70cc53 100644
--- a/build/integration/sharees_features/sharees.feature
+++ b/build/integration/sharees_features/sharees.feature
@@ -8,6 +8,14 @@ Feature: sharees
     And user "Sharee1" exists
     And group "ShareeGroup" exists
     And user "test" belongs to group "ShareeGroup"
+    And user "Sharee2" exists
+    And As an "admin"
+    And sending "PUT" to "/cloud/users/Sharee2" with
+      | key   | email |
+      | value | sharee2@system.com |
+    And sending "PUT" to "/cloud/users/Sharee2" with
+      | key   | additional_mail |
+      | value | sharee2@secondary.com |
 
   Scenario: Search without exact match
     Given As an "test"
@@ -18,7 +26,8 @@ Feature: sharees
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -34,7 +43,8 @@ Feature: sharees
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -68,7 +78,7 @@ Feature: sharees
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -85,7 +95,7 @@ Feature: sharees
     Then the OCS status code should be "100"
     And the HTTP status code should be "200"
     And "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "users" sharees returned is empty
     And "exact groups" sharees returned is empty
     And "groups" sharees returned is empty
@@ -131,7 +141,7 @@ Feature: sharees
     Then the OCS status code should be "100"
     And the HTTP status code should be "200"
     And "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "users" sharees returned is empty
     And "exact groups" sharees returned is empty
     And "groups" sharees returned is empty
@@ -162,7 +172,7 @@ Feature: sharees
     Then the OCS status code should be "100"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -177,7 +187,7 @@ Feature: sharees
     Then the OCS status code should be "100"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -207,7 +217,7 @@ Feature: sharees
     Then the OCS status code should be "100"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -254,8 +264,285 @@ Feature: sharees
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned is empty
     And "exact remotes" sharees returned is empty
     And "remotes" sharees returned is empty
+
+  Scenario: Search user by system e-mail address
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@system.com |
+      | itemType  | file |
+      | shareType | 0 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    # UserPlugin provides two identical results (except for the field order, but
+    # that is hidden by the check).
+    # MailPlugin does not add a result if there is already one for that user.
+    And "exact users" sharees returned are
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user by system e-mail address without exact match
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@system.c |
+      | itemType  | file |
+      | shareType | 0 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    # MailPlugin does not add a result if there is already one for that user.
+    And "users" sharees returned are
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user by secondary e-mail address
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@secondary.com |
+      | itemType  | file |
+      | shareType | 0 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    # UserPlugin only searches in the system e-mail address, but not in
+    # secondary addresses.
+    And "exact users" sharees returned are
+      | Sharee2 (sharee2@secondary.com) | 0 | Sharee2 | sharee2@secondary.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user by secondary e-mail address without exact match
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@secondary.c |
+      | itemType  | file |
+      | shareType | 0 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    # UserPlugin only searches in the system e-mail address, but not in
+    # secondary addresses.
+    # MailPlugin adds a result for every e-mail address of the contact unless
+    # there is an exact match.
+    And "users" sharees returned are
+      | Sharee2 (sharee2@system.com)    | 0 | Sharee2 | sharee2@system.com |
+      | Sharee2 (sharee2@secondary.com) | 0 | Sharee2 | sharee2@secondary.com |
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@unknown.com |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned are
+      | sharee2@unknown.com | 4 | sharee2@unknown.com |
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail when sharebymail app is disabled
+    Given app "sharebymail" enabled state will be restored once the scenario finishes
+    And sending "DELETE" to "/cloud/apps/sharebymail"
+    And app "sharebymail" is disabled
+    And As an "test"
+    When getting sharees for
+      | search    | sharee2@unknown.com |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail matching system e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@system.com |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail partially matching system e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@system.c |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned are
+      | sharee2@system.c | 4 | sharee2@system.c |
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail matching secondary e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@secondary.com |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search e-mail partially matching secondary e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search    | sharee2@secondary.c |
+      | itemType  | file |
+      | shareType | 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned is empty
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned are
+      | sharee2@secondary.c | 4 | sharee2@secondary.c |
+    And "emails" sharees returned is empty
+
+  Scenario: Search user and e-mail matching system e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search     | sharee2@system.com |
+      | itemType   | file |
+      | shareTypes | 0 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    # UserPlugin provides two identical results (except for the field order, but
+    # that is hidden by the check)
+    And "exact users" sharees returned are
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user and e-mail matching system e-mail address of user when sharebymail app is disabled
+    Given app "sharebymail" enabled state will be restored once the scenario finishes
+    And sending "DELETE" to "/cloud/apps/sharebymail"
+    And app "sharebymail" is disabled
+    And As an "test"
+    When getting sharees for
+      | search     | sharee2@system.com |
+      | itemType   | file |
+      | shareTypes | 0 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    # UserPlugin provides two identical results (except for the field order, but
+    # that is hidden by the check)
+    And "exact users" sharees returned are
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+      | Sharee2 | 0 | Sharee2 | sharee2@system.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user and e-mail matching secondary e-mail address of user
+    Given As an "test"
+    When getting sharees for
+      | search     | sharee2@secondary.com |
+      | itemType   | file |
+      | shareTypes | 0 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned are
+      | Sharee2 (sharee2@secondary.com) | 0 | Sharee2 | sharee2@secondary.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
+
+  Scenario: Search user and e-mail matching secondary e-mail address of user when sharebymail app is disabled
+    Given app "sharebymail" enabled state will be restored once the scenario finishes
+    And sending "DELETE" to "/cloud/apps/sharebymail"
+    And app "sharebymail" is disabled
+    And As an "test"
+    When getting sharees for
+      | search     | sharee2@secondary.com |
+      | itemType   | file |
+      | shareTypes | 0 4 |
+    Then the OCS status code should be "100"
+    And the HTTP status code should be "200"
+    And "exact users" sharees returned are
+      | Sharee2 (sharee2@secondary.com) | 0 | Sharee2 | sharee2@secondary.com |
+    And "users" sharees returned is empty
+    And "exact groups" sharees returned is empty
+    And "groups" sharees returned is empty
+    And "exact remotes" sharees returned is empty
+    And "remotes" sharees returned is empty
+    And "exact emails" sharees returned is empty
+    And "emails" sharees returned is empty
diff --git a/build/integration/sharees_features/sharees_provisioningapiv2.feature b/build/integration/sharees_features/sharees_provisioningapiv2.feature
index b27bb7a4f21..c5a42f7b6a8 100644
--- a/build/integration/sharees_features/sharees_provisioningapiv2.feature
+++ b/build/integration/sharees_features/sharees_provisioningapiv2.feature
@@ -18,7 +18,7 @@ Feature: sharees_provisioningapiv2
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -34,7 +34,7 @@ Feature: sharees_provisioningapiv2
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -68,7 +68,7 @@ Feature: sharees_provisioningapiv2
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned are
       | ShareeGroup | 1 | ShareeGroup |
@@ -114,7 +114,7 @@ Feature: sharees_provisioningapiv2
     Then the OCS status code should be "200"
     And the HTTP status code should be "200"
     And "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "users" sharees returned is empty
     And "exact groups" sharees returned is empty
     And "groups" sharees returned is empty
@@ -145,7 +145,7 @@ Feature: sharees_provisioningapiv2
     Then the OCS status code should be "200"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -160,7 +160,7 @@ Feature: sharees_provisioningapiv2
     Then the OCS status code should be "200"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -190,7 +190,7 @@ Feature: sharees_provisioningapiv2
     Then the OCS status code should be "200"
     And the HTTP status code should be "200"
     Then "exact users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     Then "users" sharees returned is empty
     Then "exact groups" sharees returned is empty
     Then "groups" sharees returned is empty
@@ -237,7 +237,7 @@ Feature: sharees_provisioningapiv2
     And the HTTP status code should be "200"
     And "exact users" sharees returned is empty
     And "users" sharees returned are
-      | Sharee1 | 0 | Sharee1 |
+      | Sharee1 | 0 | Sharee1 | Sharee1 |
     And "exact groups" sharees returned is empty
     And "groups" sharees returned is empty
     And "exact remotes" sharees returned is empty
diff --git a/lib/composer/composer/autoload_classmap.php b/lib/composer/composer/autoload_classmap.php
index 1810eab032c..16eb03b15cf 100644
--- a/lib/composer/composer/autoload_classmap.php
+++ b/lib/composer/composer/autoload_classmap.php
@@ -1202,11 +1202,13 @@ return array(
     'OC\\Collaboration\\AutoComplete\\Manager' => $baseDir . '/lib/private/Collaboration/AutoComplete/Manager.php',
     'OC\\Collaboration\\Collaborators\\GroupPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/GroupPlugin.php',
     'OC\\Collaboration\\Collaborators\\LookupPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/LookupPlugin.php',
+    'OC\\Collaboration\\Collaborators\\MailByMailPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/MailByMailPlugin.php',
     'OC\\Collaboration\\Collaborators\\MailPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/MailPlugin.php',
     'OC\\Collaboration\\Collaborators\\RemoteGroupPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/RemoteGroupPlugin.php',
     'OC\\Collaboration\\Collaborators\\RemotePlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/RemotePlugin.php',
     'OC\\Collaboration\\Collaborators\\Search' => $baseDir . '/lib/private/Collaboration/Collaborators/Search.php',
     'OC\\Collaboration\\Collaborators\\SearchResult' => $baseDir . '/lib/private/Collaboration/Collaborators/SearchResult.php',
+    'OC\\Collaboration\\Collaborators\\UserByMailPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/UserByMailPlugin.php',
     'OC\\Collaboration\\Collaborators\\UserPlugin' => $baseDir . '/lib/private/Collaboration/Collaborators/UserPlugin.php',
     'OC\\Collaboration\\Reference\\File\\FileReferenceEventListener' => $baseDir . '/lib/private/Collaboration/Reference/File/FileReferenceEventListener.php',
     'OC\\Collaboration\\Reference\\File\\FileReferenceProvider' => $baseDir . '/lib/private/Collaboration/Reference/File/FileReferenceProvider.php',
diff --git a/lib/composer/composer/autoload_static.php b/lib/composer/composer/autoload_static.php
index 753e56107d0..da38482d5ce 100644
--- a/lib/composer/composer/autoload_static.php
+++ b/lib/composer/composer/autoload_static.php
@@ -1243,11 +1243,13 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\Collaboration\\AutoComplete\\Manager' => __DIR__ . '/../../..' . '/lib/private/Collaboration/AutoComplete/Manager.php',
         'OC\\Collaboration\\Collaborators\\GroupPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/GroupPlugin.php',
         'OC\\Collaboration\\Collaborators\\LookupPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/LookupPlugin.php',
+        'OC\\Collaboration\\Collaborators\\MailByMailPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/MailByMailPlugin.php',
         'OC\\Collaboration\\Collaborators\\MailPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/MailPlugin.php',
         'OC\\Collaboration\\Collaborators\\RemoteGroupPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/RemoteGroupPlugin.php',
         'OC\\Collaboration\\Collaborators\\RemotePlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/RemotePlugin.php',
         'OC\\Collaboration\\Collaborators\\Search' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/Search.php',
         'OC\\Collaboration\\Collaborators\\SearchResult' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/SearchResult.php',
+        'OC\\Collaboration\\Collaborators\\UserByMailPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/UserByMailPlugin.php',
         'OC\\Collaboration\\Collaborators\\UserPlugin' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Collaborators/UserPlugin.php',
         'OC\\Collaboration\\Reference\\File\\FileReferenceEventListener' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Reference/File/FileReferenceEventListener.php',
         'OC\\Collaboration\\Reference\\File\\FileReferenceProvider' => __DIR__ . '/../../..' . '/lib/private/Collaboration/Reference/File/FileReferenceProvider.php',
diff --git a/lib/private/Collaboration/Collaborators/MailByMailPlugin.php b/lib/private/Collaboration/Collaborators/MailByMailPlugin.php
new file mode 100644
index 00000000000..53f90e33c57
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/MailByMailPlugin.php
@@ -0,0 +1,45 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\Collaboration\Collaborators;
+
+use OC\KnownUser\KnownUserService;
+use OCP\Contacts\IManager;
+use OCP\Federation\ICloudIdManager;
+use OCP\IConfig;
+use OCP\IGroupManager;
+use OCP\IUserSession;
+use OCP\Mail\IEmailValidator;
+use OCP\Share\IShare;
+
+/**
+ * Dummy subclass to initialize a MailPlugin with a specific share type.
+ */
+class MailByMailPlugin extends MailPlugin {
+
+	public function __construct(
+		IManager $contactsManager,
+		ICloudIdManager $cloudIdManager,
+		IConfig $config,
+		IGroupManager $groupManager,
+		KnownUserService $knownUserService,
+		IUserSession $userSession,
+		IEmailValidator $emailValidator,
+		mixed $shareWithGroupOnlyExcludeGroupsList = [],
+	) {
+		parent::__construct(
+			$contactsManager,
+			$cloudIdManager,
+			$config,
+			$groupManager,
+			$knownUserService,
+			$userSession,
+			$emailValidator,
+			$shareWithGroupOnlyExcludeGroupsList,
+			IShare::TYPE_EMAIL,
+		);
+	}
+}
diff --git a/lib/private/Collaboration/Collaborators/MailPlugin.php b/lib/private/Collaboration/Collaborators/MailPlugin.php
index ba4f411092b..84ff487203f 100644
--- a/lib/private/Collaboration/Collaborators/MailPlugin.php
+++ b/lib/private/Collaboration/Collaborators/MailPlugin.php
@@ -41,7 +41,8 @@ class MailPlugin implements ISearchPlugin {
 		private KnownUserService $knownUserService,
 		private IUserSession $userSession,
 		private IEmailValidator $emailValidator,
-		private mixed $shareWithGroupOnlyExcludeGroupsList = [],
+		private mixed $shareWithGroupOnlyExcludeGroupsList,
+		private int $shareType,
 	) {
 		$this->shareeEnumeration = $this->config->getAppValue('core', 'shareapi_allow_share_dialog_user_enumeration', 'yes') === 'yes';
 		$this->shareWithGroupOnly = $this->config->getAppValue('core', 'shareapi_only_share_with_group_members', 'no') === 'yes';
@@ -139,7 +140,7 @@ class MailPlugin implements ISearchPlugin {
 								continue;
 							}
 
-							if (!$this->isCurrentUser($cloud) && !$searchResult->hasResult($userType, $cloud->getUser())) {
+							if ($this->shareType === IShare::TYPE_USER && !$this->isCurrentUser($cloud) && !$searchResult->hasResult($userType, $cloud->getUser())) {
 								$singleResult = [[
 									'label' => $displayName,
 									'uuid' => $contact['UID'] ?? $emailAddress,
@@ -183,22 +184,28 @@ class MailPlugin implements ISearchPlugin {
 								}
 							}
 							if ($addToWide && !$this->isCurrentUser($cloud) && !$searchResult->hasResult($userType, $cloud->getUser())) {
-								$userResults['wide'][] = [
-									'label' => $displayName,
-									'uuid' => $contact['UID'] ?? $emailAddress,
-									'name' => $contact['FN'] ?? $displayName,
-									'value' => [
-										'shareType' => IShare::TYPE_USER,
-										'shareWith' => $cloud->getUser(),
-									],
-									'shareWithDisplayNameUnique' => !empty($emailAddress) ? $emailAddress : $cloud->getUser()
-								];
+								if ($this->shareType === IShare::TYPE_USER) {
+									$userResults['wide'][] = [
+										'label' => $displayName,
+										'uuid' => $contact['UID'] ?? $emailAddress,
+										'name' => $contact['FN'] ?? $displayName,
+										'value' => [
+											'shareType' => IShare::TYPE_USER,
+											'shareWith' => $cloud->getUser(),
+										],
+										'shareWithDisplayNameUnique' => !empty($emailAddress) ? $emailAddress : $cloud->getUser()
+									];
+								}
 								continue;
 							}
 						}
 						continue;
 					}
 
+					if ($this->shareType !== IShare::TYPE_EMAIL) {
+						continue;
+					}
+
 					if ($exactEmailMatch
 						|| (isset($contact['FN']) && strtolower($contact['FN']) === $lowerSearch)) {
 						if ($exactEmailMatch) {
@@ -239,7 +246,8 @@ class MailPlugin implements ISearchPlugin {
 			$userResults['wide'] = array_slice($userResults['wide'], $offset, $limit);
 		}
 
-		if (!$searchResult->hasExactIdMatch($emailType) && $this->emailValidator->isValid($search)) {
+		if ($this->shareType === IShare::TYPE_EMAIL
+				&& !$searchResult->hasExactIdMatch($emailType) && $this->emailValidator->isValid($search)) {
 			$result['exact'][] = [
 				'label' => $search,
 				'uuid' => $search,
@@ -250,10 +258,12 @@ class MailPlugin implements ISearchPlugin {
 			];
 		}
 
-		if (!empty($userResults['wide'])) {
+		if ($this->shareType === IShare::TYPE_USER && !empty($userResults['wide'])) {
 			$searchResult->addResultSet($userType, $userResults['wide'], []);
 		}
-		$searchResult->addResultSet($emailType, $result['wide'], $result['exact']);
+		if ($this->shareType === IShare::TYPE_EMAIL) {
+			$searchResult->addResultSet($emailType, $result['wide'], $result['exact']);
+		}
 
 		return !$reachedEnd;
 	}
diff --git a/lib/private/Collaboration/Collaborators/UserByMailPlugin.php b/lib/private/Collaboration/Collaborators/UserByMailPlugin.php
new file mode 100644
index 00000000000..44c1a95221c
--- /dev/null
+++ b/lib/private/Collaboration/Collaborators/UserByMailPlugin.php
@@ -0,0 +1,45 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\Collaboration\Collaborators;
+
+use OC\KnownUser\KnownUserService;
+use OCP\Contacts\IManager;
+use OCP\Federation\ICloudIdManager;
+use OCP\IConfig;
+use OCP\IGroupManager;
+use OCP\IUserSession;
+use OCP\Mail\IEmailValidator;
+use OCP\Share\IShare;
+
+/**
+ * Dummy subclass to initialize a MailPlugin with a specific share type.
+ */
+class UserByMailPlugin extends MailPlugin {
+
+	public function __construct(
+		IManager $contactsManager,
+		ICloudIdManager $cloudIdManager,
+		IConfig $config,
+		IGroupManager $groupManager,
+		KnownUserService $knownUserService,
+		IUserSession $userSession,
+		IEmailValidator $emailValidator,
+		mixed $shareWithGroupOnlyExcludeGroupsList = [],
+	) {
+		parent::__construct(
+			$contactsManager,
+			$cloudIdManager,
+			$config,
+			$groupManager,
+			$knownUserService,
+			$userSession,
+			$emailValidator,
+			$shareWithGroupOnlyExcludeGroupsList,
+			IShare::TYPE_USER,
+		);
+	}
+}
diff --git a/lib/private/Server.php b/lib/private/Server.php
index 9799aeb9bd1..f3997759539 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -25,9 +25,10 @@ use OC\Authentication\Token\IProvider;
 use OC\Avatar\AvatarManager;
 use OC\Blurhash\Listener\GenerateBlurhashMetadata;
 use OC\Collaboration\Collaborators\GroupPlugin;
-use OC\Collaboration\Collaborators\MailPlugin;
+use OC\Collaboration\Collaborators\MailByMailPlugin;
 use OC\Collaboration\Collaborators\RemoteGroupPlugin;
 use OC\Collaboration\Collaborators\RemotePlugin;
+use OC\Collaboration\Collaborators\UserByMailPlugin;
 use OC\Collaboration\Collaborators\UserPlugin;
 use OC\Collaboration\Reference\ReferenceManager;
 use OC\Command\CronBus;
@@ -1112,8 +1113,9 @@ class Server extends ServerContainer implements IServerContainer {
 
 			// register default plugins
 			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_USER', 'class' => UserPlugin::class]);
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_USER', 'class' => UserByMailPlugin::class]);
 			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_GROUP', 'class' => GroupPlugin::class]);
-			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_EMAIL', 'class' => MailPlugin::class]);
+			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_EMAIL', 'class' => MailByMailPlugin::class]);
 			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_REMOTE', 'class' => RemotePlugin::class]);
 			$instance->registerPlugin(['shareType' => 'SHARE_TYPE_REMOTE_GROUP', 'class' => RemoteGroupPlugin::class]);
 
diff --git a/tests/lib/Collaboration/Collaborators/MailPluginTest.php b/tests/lib/Collaboration/Collaborators/MailPluginTest.php
index 6c81a0d68e2..e6580854784 100644
--- a/tests/lib/Collaboration/Collaborators/MailPluginTest.php
+++ b/tests/lib/Collaboration/Collaborators/MailPluginTest.php
@@ -72,7 +72,7 @@ class MailPluginTest extends TestCase {
 		$this->searchResult = new SearchResult();
 	}
 
-	public function instantiatePlugin() {
+	public function instantiatePlugin(int $shareType) {
 		$this->plugin = new MailPlugin(
 			$this->contactsManager,
 			$this->cloudIdManager,
@@ -81,6 +81,8 @@ class MailPluginTest extends TestCase {
 			$this->knownUserService,
 			$this->userSession,
 			$this->getEmailValidatorWithStrictEmailCheck(),
+			[],
+			$shareType,
 		);
 	}
 
@@ -89,11 +91,13 @@ class MailPluginTest extends TestCase {
 	 * @param string $searchTerm
 	 * @param array $contacts
 	 * @param bool $shareeEnumeration
-	 * @param array $expected
-	 * @param bool $reachedEnd
+	 * @param array $expectedResult
+	 * @param bool $expectedExactIdMatch
+	 * @param bool $expectedMoreResults
+	 * @param bool $validEmail
 	 */
-	#[\PHPUnit\Framework\Attributes\DataProvider('dataGetEmail')]
-	public function testSearch($searchTerm, $contacts, $shareeEnumeration, $expected, $exactIdMatch, $reachedEnd, $validEmail): void {
+	#[\PHPUnit\Framework\Attributes\DataProvider('dataSearchEmail')]
+	public function testSearchEmail($searchTerm, $contacts, $shareeEnumeration, $expectedResult, $expectedExactIdMatch, $expectedMoreResults, $validEmail): void {
 		$this->config->expects($this->any())
 			->method('getAppValue')
 			->willReturnCallback(
@@ -105,7 +109,7 @@ class MailPluginTest extends TestCase {
 				}
 			);
 
-		$this->instantiatePlugin();
+		$this->instantiatePlugin(IShare::TYPE_EMAIL);
 
 		$currentUser = $this->createMock(IUser::class);
 		$currentUser->method('getUID')
@@ -125,12 +129,12 @@ class MailPluginTest extends TestCase {
 		$moreResults = $this->plugin->search($searchTerm, 2, 0, $this->searchResult);
 		$result = $this->searchResult->asArray();
 
-		$this->assertSame($exactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
-		$this->assertEquals($expected, $result);
-		$this->assertSame($reachedEnd, $moreResults);
+		$this->assertSame($expectedExactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
+		$this->assertEquals($expectedResult, $result);
+		$this->assertSame($expectedMoreResults, $moreResults);
 	}
 
-	public static function dataGetEmail(): array {
+	public static function dataSearchEmail(): array {
 		return [
 			// data set 0
 			['test', [], true, ['emails' => [], 'exact' => ['emails' => []]], false, false, false],
@@ -396,7 +400,7 @@ class MailPluginTest extends TestCase {
 				false,
 			],
 			// data set 13
-			// Local user found by email
+			// Local user found by email => no result
 			[
 				'test@example.com',
 				[
@@ -409,8 +413,8 @@ class MailPluginTest extends TestCase {
 					]
 				],
 				false,
-				['users' => [], 'exact' => ['users' => [['uuid' => 'uid1', 'name' => 'User', 'label' => 'User (test@example.com)','value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test'], 'shareWithDisplayNameUnique' => 'test@example.com']]]],
-				true,
+				['exact' => []],
+				false,
 				false,
 				true,
 			],
@@ -434,7 +438,7 @@ class MailPluginTest extends TestCase {
 				true,
 			],
 			// data set 15
-			// Pagination and "more results" for user matches byyyyyyy emails
+			// Several local users found by email => no result nor pagination
 			[
 				'test@example',
 				[
@@ -468,12 +472,9 @@ class MailPluginTest extends TestCase {
 					],
 				],
 				true,
-				['users' => [
-					['uuid' => 'uid1', 'name' => 'User1', 'label' => 'User1 (test@example.com)', 'value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test1'], 'shareWithDisplayNameUnique' => 'test@example.com'],
-					['uuid' => 'uid2', 'name' => 'User2', 'label' => 'User2 (test@example.de)', 'value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test2'], 'shareWithDisplayNameUnique' => 'test@example.de'],
-				], 'emails' => [], 'exact' => ['users' => [], 'emails' => []]],
+				['emails' => [], 'exact' => ['emails' => []]],
+				false,
 				false,
-				true,
 				false,
 			],
 			// data set 16
@@ -567,13 +568,310 @@ class MailPluginTest extends TestCase {
 	 *
 	 * @param string $searchTerm
 	 * @param array $contacts
-	 * @param array $expected
-	 * @param bool $exactIdMatch
-	 * @param bool $reachedEnd
-	 * @param array groups
+	 * @param bool $shareeEnumeration
+	 * @param array $expectedResult
+	 * @param bool $expectedExactIdMatch
+	 * @param bool $expectedMoreResults
+	 */
+	#[\PHPUnit\Framework\Attributes\DataProvider('dataSearchUser')]
+	public function testSearchUser($searchTerm, $contacts, $shareeEnumeration, $expectedResult, $expectedExactIdMatch, $expectedMoreResults): void {
+		$this->config->expects($this->any())
+			->method('getAppValue')
+			->willReturnCallback(
+				function ($appName, $key, $default) use ($shareeEnumeration) {
+					if ($appName === 'core' && $key === 'shareapi_allow_share_dialog_user_enumeration') {
+						return $shareeEnumeration ? 'yes' : 'no';
+					}
+					return $default;
+				}
+			);
+
+		$this->instantiatePlugin(IShare::TYPE_USER);
+
+		$currentUser = $this->createMock(IUser::class);
+		$currentUser->method('getUID')
+			->willReturn('current');
+		$this->userSession->method('getUser')
+			->willReturn($currentUser);
+
+		$this->contactsManager->expects($this->any())
+			->method('search')
+			->willReturnCallback(function ($search, $searchAttributes) use ($searchTerm, $contacts) {
+				if ($search === $searchTerm) {
+					return $contacts;
+				}
+				return [];
+			});
+
+		$moreResults = $this->plugin->search($searchTerm, 2, 0, $this->searchResult);
+		$result = $this->searchResult->asArray();
+
+		$this->assertSame($expectedExactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
+		$this->assertEquals($expectedResult, $result);
+		$this->assertSame($expectedMoreResults, $moreResults);
+	}
+
+	public static function dataSearchUser(): array {
+		return [
+			// data set 0
+			['test', [], true, ['exact' => []], false, false],
+			// data set 1
+			['test', [], false, ['exact' => []], false, false],
+			// data set 2
+			[
+				'test@remote.com',
+				[],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 3
+			[
+				'test@remote.com',
+				[],
+				false,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 4
+			[
+				'test',
+				[
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3 @ Localhost',
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2 @ Localhost',
+						'EMAIL' => [
+						],
+					],
+					[
+						'UID' => 'uid1',
+						'FN' => 'User @ Localhost',
+						'EMAIL' => [
+							'username@localhost',
+						],
+					],
+				],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 5
+			[
+				'test',
+				[
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3 @ Localhost',
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2 @ Localhost',
+						'EMAIL' => [
+						],
+					],
+					[
+						'isLocalSystemBook' => true,
+						'UID' => 'uid1',
+						'FN' => 'User @ Localhost',
+						'EMAIL' => [
+							'username@localhost',
+						],
+					],
+				],
+				false,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 6
+			[
+				'test@remote.com',
+				[
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3 @ Localhost',
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2 @ Localhost',
+						'EMAIL' => [
+						],
+					],
+					[
+						'UID' => 'uid1',
+						'FN' => 'User @ Localhost',
+						'EMAIL' => [
+							'username@localhost',
+						],
+					],
+				],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 7
+			[
+				'username@localhost',
+				[
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3 @ Localhost',
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2 @ Localhost',
+						'EMAIL' => [
+						],
+					],
+					[
+						'UID' => 'uid1',
+						'FN' => 'User @ Localhost',
+						'EMAIL' => [
+							'username@localhost',
+						],
+					],
+				],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 8
+			// Local user found by email
+			[
+				'test@example.com',
+				[
+					[
+						'UID' => 'uid1',
+						'FN' => 'User',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test@localhost'],
+						'isLocalSystemBook' => true,
+					]
+				],
+				false,
+				['users' => [], 'exact' => ['users' => [['uuid' => 'uid1', 'name' => 'User', 'label' => 'User (test@example.com)','value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test'], 'shareWithDisplayNameUnique' => 'test@example.com']]]],
+				true,
+				false,
+			],
+			// data set 9
+			// Current local user found by email => no result
+			[
+				'test@example.com',
+				[
+					[
+						'UID' => 'uid1',
+						'FN' => 'User',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['current@localhost'],
+						'isLocalSystemBook' => true,
+					]
+				],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+			// data set 10
+			// Pagination and "more results" for user matches by emails
+			[
+				'test@example',
+				[
+					[
+						'UID' => 'uid1',
+						'FN' => 'User1',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test1@localhost'],
+						'isLocalSystemBook' => true,
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2',
+						'EMAIL' => ['test@example.de'],
+						'CLOUD' => ['test2@localhost'],
+						'isLocalSystemBook' => true,
+					],
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3',
+						'EMAIL' => ['test@example.org'],
+						'CLOUD' => ['test3@localhost'],
+						'isLocalSystemBook' => true,
+					],
+					[
+						'UID' => 'uid4',
+						'FN' => 'User4',
+						'EMAIL' => ['test@example.net'],
+						'CLOUD' => ['test4@localhost'],
+						'isLocalSystemBook' => true,
+					],
+				],
+				true,
+				['users' => [
+					['uuid' => 'uid1', 'name' => 'User1', 'label' => 'User1 (test@example.com)', 'value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test1'], 'shareWithDisplayNameUnique' => 'test@example.com'],
+					['uuid' => 'uid2', 'name' => 'User2', 'label' => 'User2 (test@example.de)', 'value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test2'], 'shareWithDisplayNameUnique' => 'test@example.de'],
+				], 'exact' => ['users' => []]],
+				false,
+				true,
+			],
+			// data set 11
+			// Pagination and "more results" for normal emails
+			[
+				'test@example',
+				[
+					[
+						'UID' => 'uid1',
+						'FN' => 'User1',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test1@localhost'],
+					],
+					[
+						'UID' => 'uid2',
+						'FN' => 'User2',
+						'EMAIL' => ['test@example.de'],
+						'CLOUD' => ['test2@localhost'],
+					],
+					[
+						'UID' => 'uid3',
+						'FN' => 'User3',
+						'EMAIL' => ['test@example.org'],
+						'CLOUD' => ['test3@localhost'],
+					],
+					[
+						'UID' => 'uid4',
+						'FN' => 'User4',
+						'EMAIL' => ['test@example.net'],
+						'CLOUD' => ['test4@localhost'],
+					],
+				],
+				true,
+				['exact' => []],
+				false,
+				false,
+			],
+		];
+	}
+
+	/**
+	 *
+	 * @param string $searchTerm
+	 * @param array $contacts
+	 * @param array $expectedResult
+	 * @param bool $expectedExactIdMatch
+	 * @param bool $expectedMoreResults
+	 * @param array $userToGroupMapping
+	 * @param bool $validEmail
 	 */
-	#[\PHPUnit\Framework\Attributes\DataProvider('dataGetEmailGroupsOnly')]
-	public function testSearchGroupsOnly($searchTerm, $contacts, $expected, $exactIdMatch, $reachedEnd, $userToGroupMapping, $validEmail): void {
+	#[\PHPUnit\Framework\Attributes\DataProvider('dataSearchEmailGroupsOnly')]
+	public function testSearchEmailGroupsOnly($searchTerm, $contacts, $expectedResult, $expectedExactIdMatch, $expectedMoreResults, $userToGroupMapping, $validEmail): void {
 		$this->config->expects($this->any())
 			->method('getAppValue')
 			->willReturnCallback(
@@ -587,7 +885,7 @@ class MailPluginTest extends TestCase {
 				}
 			);
 
-		$this->instantiatePlugin();
+		$this->instantiatePlugin(IShare::TYPE_EMAIL);
 
 		/** @var IUser|\PHPUnit\Framework\MockObject\MockObject */
 		$currentUser = $this->createMock('\OCP\IUser');
@@ -624,12 +922,12 @@ class MailPluginTest extends TestCase {
 		$moreResults = $this->plugin->search($searchTerm, 2, 0, $this->searchResult);
 		$result = $this->searchResult->asArray();
 
-		$this->assertSame($exactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
-		$this->assertEquals($expected, $result);
-		$this->assertSame($reachedEnd, $moreResults);
+		$this->assertSame($expectedExactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
+		$this->assertEquals($expectedResult, $result);
+		$this->assertSame($expectedMoreResults, $moreResults);
 	}
 
-	public static function dataGetEmailGroupsOnly(): array {
+	public static function dataSearchEmailGroupsOnly(): array {
 		return [
 			// The user `User` can share with the current user
 			[
@@ -640,15 +938,15 @@ class MailPluginTest extends TestCase {
 						'EMAIL' => ['test@example.com'],
 						'CLOUD' => ['test@localhost'],
 						'isLocalSystemBook' => true,
-						'UID' => 'User'
+						'UID' => 'User',
 					]
 				],
-				['users' => [['label' => 'User (test@example.com)', 'uuid' => 'User', 'name' => 'User', 'value' => ['shareType' => 0, 'shareWith' => 'test'],'shareWithDisplayNameUnique' => 'test@example.com',]], 'emails' => [], 'exact' => ['emails' => [], 'users' => []]],
+				['emails' => [], 'exact' => ['emails' => []]],
 				false,
 				false,
 				[
 					'currentUser' => ['group1'],
-					'User' => ['group1']
+					'User' => ['group1'],
 				],
 				false,
 			],
@@ -661,7 +959,7 @@ class MailPluginTest extends TestCase {
 						'EMAIL' => ['test@example.com'],
 						'CLOUD' => ['test@localhost'],
 						'isLocalSystemBook' => true,
-						'UID' => 'User'
+						'UID' => 'User',
 					]
 				],
 				['emails' => [], 'exact' => ['emails' => []]],
@@ -669,7 +967,7 @@ class MailPluginTest extends TestCase {
 				false,
 				[
 					'currentUser' => ['group1'],
-					'User' => ['group2']
+					'User' => ['group2'],
 				],
 				false,
 			],
@@ -682,18 +980,149 @@ class MailPluginTest extends TestCase {
 						'EMAIL' => ['test@example.com'],
 						'CLOUD' => ['test@localhost'],
 						'isLocalSystemBook' => true,
-						'UID' => 'User'
+						'UID' => 'User',
 					]
 				],
-				['emails' => [], 'exact' => ['emails' => [['label' => 'test@example.com', 'uuid' => 'test@example.com', 'value' => ['shareType' => 4,'shareWith' => 'test@example.com']]]]],
+				['emails' => [], 'exact' => ['emails' => [['label' => 'test@example.com', 'uuid' => 'test@example.com', 'value' => ['shareType' => IShare::TYPE_EMAIL,'shareWith' => 'test@example.com']]]]],
 				false,
 				false,
 				[
 					'currentUser' => ['group1'],
-					'User' => ['group2']
+					'User' => ['group2'],
 				],
 				true,
 			]
 		];
 	}
+
+	/**
+	 *
+	 * @param string $searchTerm
+	 * @param array $contacts
+	 * @param array $expectedResult
+	 * @param bool $expectedExactIdMatch
+	 * @param bool $expectedMoreResults
+	 * @param array $userToGroupMapping
+	 */
+	#[\PHPUnit\Framework\Attributes\DataProvider('dataSearchUserGroupsOnly')]
+	public function testSearchUserGroupsOnly($searchTerm, $contacts, $expectedResult, $expectedExactIdMatch, $expectedMoreResults, $userToGroupMapping): void {
+		$this->config->expects($this->any())
+			->method('getAppValue')
+			->willReturnCallback(
+				function ($appName, $key, $default) {
+					if ($appName === 'core' && $key === 'shareapi_allow_share_dialog_user_enumeration') {
+						return 'yes';
+					} elseif ($appName === 'core' && $key === 'shareapi_only_share_with_group_members') {
+						return 'yes';
+					}
+					return $default;
+				}
+			);
+
+		$this->instantiatePlugin(IShare::TYPE_USER);
+
+		/** @var \OCP\IUser | \PHPUnit\Framework\MockObject\MockObject */
+		$currentUser = $this->createMock('\OCP\IUser');
+
+		$currentUser->expects($this->any())
+			->method('getUID')
+			->willReturn('currentUser');
+
+		$this->contactsManager->expects($this->any())
+			->method('search')
+			->willReturnCallback(function ($search, $searchAttributes) use ($searchTerm, $contacts) {
+				if ($search === $searchTerm) {
+					return $contacts;
+				}
+				return [];
+			});
+
+		$this->userSession->expects($this->any())
+			->method('getUser')
+			->willReturn($currentUser);
+
+		$this->groupManager->expects($this->any())
+			->method('getUserGroupIds')
+			->willReturnCallback(function (\OCP\IUser $user) use ($userToGroupMapping) {
+				return $userToGroupMapping[$user->getUID()];
+			});
+
+		$this->groupManager->expects($this->any())
+			->method('isInGroup')
+			->willReturnCallback(function ($userId, $group) use ($userToGroupMapping) {
+				return in_array($group, $userToGroupMapping[$userId]);
+			});
+
+		$moreResults = $this->plugin->search($searchTerm, 2, 0, $this->searchResult);
+		$result = $this->searchResult->asArray();
+
+		$this->assertSame($expectedExactIdMatch, $this->searchResult->hasExactIdMatch(new SearchResultType('emails')));
+		$this->assertEquals($expectedResult, $result);
+		$this->assertSame($expectedMoreResults, $moreResults);
+	}
+
+	public static function dataSearchUserGroupsOnly(): array {
+		return [
+			// The user `User` can share with the current user
+			[
+				'test',
+				[
+					[
+						'FN' => 'User',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test@localhost'],
+						'isLocalSystemBook' => true,
+						'UID' => 'User',
+					]
+				],
+				['users' => [['label' => 'User (test@example.com)', 'uuid' => 'User', 'name' => 'User', 'value' => ['shareType' => IShare::TYPE_USER, 'shareWith' => 'test'],'shareWithDisplayNameUnique' => 'test@example.com',]], 'exact' => ['users' => []]],
+				false,
+				false,
+				[
+					'currentUser' => ['group1'],
+					'User' => ['group1'],
+				],
+			],
+			// The user `User` cannot share with the current user
+			[
+				'test',
+				[
+					[
+						'FN' => 'User',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test@localhost'],
+						'isLocalSystemBook' => true,
+						'UID' => 'User',
+					]
+				],
+				['exact' => []],
+				false,
+				false,
+				[
+					'currentUser' => ['group1'],
+					'User' => ['group2'],
+				],
+			],
+			// The user `User` cannot share with the current user, but there is an exact match on the e-mail address -> share by e-mail
+			[
+				'test@example.com',
+				[
+					[
+						'FN' => 'User',
+						'EMAIL' => ['test@example.com'],
+						'CLOUD' => ['test@localhost'],
+						'isLocalSystemBook' => true,
+						'UID' => 'User',
+					]
+				],
+				['exact' => []],
+				false,
+				false,
+				[
+					'currentUser' => ['group1'],
+					'User' => ['group2'],
+				],
+			]
+		];
+	}
 }