fix: choppy cursor selection performance issue

src/editor/EditorManager.js

@@ -775,7 +775,7 @@ define(function (require, exports, module) {
 
     // Set up event dispatching
     EventDispatcher.makeEventDispatcher(exports);
-    EventDispatcher.setLeakThresholdForEvent(EVENT_ACTIVE_EDITOR_CHANGED, 25);
+    EventDispatcher.setLeakThresholdForEvent(EVENT_ACTIVE_EDITOR_CHANGED, 30);
 
     // File-based preferences handling
     exports.on(EVENT_ACTIVE_EDITOR_CHANGED, function (e, current) {

src/extensions/default/Git/src/GutterManager.js

@@ -49,6 +49,11 @@ define(function (require, exports) {
 
     function _cursorActivity(_evt, editor){
         // this is to prevent a gutter gap in the active line if there is no color on this line.
+        if (editor.hasSelection()){
+            // we dont show the gutter gap color when there is a selection. also adding dummy gutter is expensive
+            // and make test selection with cursor choppy
+            return;
+        }
         _addDummyGutterMarkerIfNotExist(editor._codeMirror, editor.getCursorPos().line);
     }
 

src/extensionsIntegrated/CSSColorPreview/main.js

@@ -213,6 +213,11 @@ define(function (require, exports, module) {
 
     function _cursorActivity(_evt, editor){
         // this is to prevent a gutter gap in the active line if there is no color on this line.
+        if(editor.hasSelection()){
+            // we dont show the gutter gap color when there is a selection. also adding dummy gutter is expensive
+            // and make test selection with cursor choppy
+            return;
+        }
         _addDummyGutterMarkerIfNotExist(editor, editor.getCursorPos().line);
         if(editor._currentlyColorMarkedLine){
             editor.clearAllMarks(COLOR_MARK_NAME);

src/extensionsIntegrated/HtmlTagSyncEdit/main.js

@@ -237,7 +237,9 @@ define(function (require, exports, module) {
 
     function cursorActivity() {
         const cursor = activeEditor.getCursorPos();
-        if(activeEditor.hasMultipleCursors()){
+        const sel = activeEditor.getSelection();
+        const multiLineSelection = sel.start.line !== sel.end.line;
+        if(activeEditor.hasMultipleCursors() || multiLineSelection){
             clearRenameMarkers();
             return;
         }