added more placement points for custom widgets

src/public/javascripts/services/frontend_script_api.js

@@ -11,6 +11,9 @@ import CollapsibleWidget from '../widgets/collapsible_widget.js';
 import ws from "./ws.js";
 import hoistedNoteService from "./hoisted_note.js";
 import appContext from "./app_context.js";
+import TabAwareWidget from "../widgets/tab_aware_widget.js";
+import TabCachingWidget from "../widgets/tab_caching_widget.js";
+import BasicWidget from "../widgets/basic_widget.js";
 
 /**
  * This is the main frontend API interface for scripts. It's published in the local "api" object.
@@ -37,6 +40,15 @@ function FrontendScriptApi(startNote, currentNote, originEntity = null, $contain
     /** @property {CollapsibleWidget} */
     this.CollapsibleWidget = CollapsibleWidget;
 
+    /** @property {TabAwareWidget} */
+    this.TabAwareWidget = TabAwareWidget;
+
+    /** @property {TabCachingWidget} */
+    this.TabCachingWidget = TabCachingWidget;
+
+    /** @property {BasicWidget} */
+    this.BasicWidget = BasicWidget;
+
     /**
      * Activates note in the tree and in the note detail.
      *

src/public/javascripts/widgets/desktop_layout.js

@@ -124,6 +124,7 @@ export default class DesktopLayout {
                     .child(new SearchBoxWidget())
                     .child(new SearchResultsWidget())
                     .child(appContext.mainTreeWidget)
+                    .child(...this.customWidgets.get('left-pane'))
                 )
                 .child(new FlexContainer('column').id('center-pane')
                     .child(new FlexContainer('row').class('title-row')
@@ -137,6 +138,7 @@ export default class DesktopLayout {
                     )
                     .child(new TabCachingWidget(() => new PromotedAttributesWidget()))
                     .child(new TabCachingWidget(() => new NoteDetailWidget()))
+                    .child(...this.customWidgets.get('center-pane'))
                 )
                 .child(new SidePaneContainer('right')
                     .cssBlock(RIGHT_PANE_CSS)