Fix incorrect command palette cursor position

Fixes #6011

Fixes incorrect command palette cursor position especially on Safari browser.
Added additional handling to verify that if no selection is currently present,
force the cursor at the end of the input. Inspired by a similar implementation
in VS Code.

Signed-off-by: Vincent Fugnitto <vincent.fugnitto@ericsson.com>

packages/monaco/src/browser/monaco-quick-open-service.ts

@@ -135,6 +135,10 @@ export class MonacoQuickOpenService extends QuickOpenService {
         const widget = this.widget;
         if (widget.inputBox) {
             widget.inputBox.inputElement.tabIndex = 1;
+            // Position the cursor at the end of the input unless a user has made a selection.
+            if (widget.inputBox.inputElement.selectionStart === widget.inputBox.inputElement.selectionEnd) {
+                widget.inputBox.inputElement.selectionStart = widget.inputBox.inputElement.value.length;
+            }
         }
     }