Memory leak in settings editor

[SimonSiefke]

Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: 1.90.2
• OS Version: Ubuntu 24.04

Steps to Reproduce:

1. Open the settings ui editor
2. Close the settings ui editor
3. Repeat a few times
4. Notice that the number the number of SettingsEditor2Input and Settings2EditorModel grows by 1 each time, for example, opening and closing the settings editor 197 times, increases the number of SettingsEditor2Input and Settings2EditorModel by 197:

{
  "instanceCountsDifferenceWithSourceMap": [
    {
      "name": "DisposableStore",
      "count": 15109,
      "beforeCount": 4773,
      "url": "/src/vs/base/common/lifecycle.ts:370:1"
    },
    {
      "name": "Emitter",
      "count": 14937,
      "beforeCount": 4793,
      "url": "/src/vs/base/common/event.ts:1020:13"
    },
    {
      "name": "LeakageMonitor",
      "count": 14891,
      "beforeCount": 4747,
      "url": "/src/vs/base/common/event.ts:838:19"
    },
    {
      "name": "SettingsTreeSettingElement",
      "count": 9802,
      "beforeCount": 1430,
      "url": "/src/vs/workbench/contrib/preferences/browser/settingsTreeModels.ts:168:2"
    },
    {
      "name": "Node",
      "count": 6289,
      "beforeCount": 6285,
      "url": "/src/vs/base/common/linkedList.ts:14:13"
    },
    {
      "name": "UniqueContainer",
      "count": 3986,
      "beforeCount": 3715,
      "url": "/src/vs/base/common/event.ts:934:29"
    },
    {
      "name": "DomListener",
      "count": 2680,
      "beforeCount": 2187,
      "url": "/src/vs/base/browser/dom.ts:138:13"
    },
    {
      "name": "KeyCodeChord",
      "count": 1070,
      "beforeCount": 1069,
      "url": "/src/vs/base/common/keybindings.ts:82:18"
    },
    {
      "name": "EventDeliveryQueuePrivate",
      "count": 1030,
      "beforeCount": 445,
      "url": "/src/vs/base/common/event.ts:1248:0"
    },
    {
      "name": "Uri",
      "count": 816,
      "beforeCount": 619,
      "url": "/src/vs/base/common/uri.ts:447:0"
    },
    {
      "name": "ContextKey",
      "count": 561,
      "beforeCount": 560,
      "url": "/src/vs/platform/contextkey/browser/contextKeyService.ts:199:13"
    },
    {
      "name": "SettingsTreeGroupElement",
      "count": 535,
      "beforeCount": 79,
      "url": "/src/vs/workbench/contrib/preferences/browser/settingsTreeModels.ts:88:13"
    },
    {
      "name": "MenuItemAction",
      "count": 332,
      "beforeCount": 258,
      "url": "/src/vs/platform/actions/common/actions.ts:482:2"
    },
    {
      "name": "Action",
      "count": 292,
      "beforeCount": 241,
      "url": "/src/vs/base/common/actions.ts:68:13"
    },
    {
      "name": "DomEmitter",
      "count": 241,
      "beforeCount": 233,
      "url": "/src/vs/base/browser/event.ts:39:13"
    },
    {
      "name": "SettingsEditor2Input",
      "count": 200,
      "beforeCount": 3,
      "url": "/src/vs/workbench/services/preferences/common/preferencesEditorInput.ts:30:23"
    },
    {
      "name": "Settings2EditorModel",
      "count": 200,
      "beforeCount": 3,
      "url": "/src/vs/workbench/services/preferences/common/preferencesModels.ts:224:10"
    },
    {
      "name": "MutableDisposable",
      "count": 171,
      "beforeCount": 163,
      "url": "/src/vs/base/common/lifecycle.ts:511:1"
    },
    {
      "name": "DisposableMap",
      "count": 116,
      "beforeCount": 115,
      "url": "/src/vs/base/common/lifecycle.ts:718:1"
    },
    {
      "name": "Separator",
      "count": 113,
      "beforeCount": 78,
      "url": "/src/vs/base/common/actions.ts:198:0"
    },
    {
      "name": "Lazy",
      "count": 111,
      "beforeCount": 78,
      "url": "/src/vs/base/common/lazy.ts:13:19"
    },
    {
      "name": "RunOnceScheduler",
      "count": 105,
      "beforeCount": 98,
      "url": "/src/vs/base/common/async.ts:975:13"
    },
    {
      "name": "FocusTracker",
      "count": 82,
      "beforeCount": 81,
      "url": "/src/vs/base/browser/dom.ts:1334:13"
    },
    {
      "name": "DebugNameData",
      "count": 74,
      "beforeCount": 52,
      "url": "/src/vs/base/common/observableInternal/debugName.ts:28:18"
    },
    {
      "name": "ConfigurationInspectValue",
      "count": 65,
      "beforeCount": 17,
      "url": "/src/vs/platform/configuration/common/configurationModels.ts:511:19"
    }
  ]
}

Test script

git clone git@github.com:SimonSiefke/vscode-memory-leak-finder.git &&
cd vscode-memory-leak-finder &&
git checkout v5.46.0 &&
npm ci &&
node packages/cli/bin/test.js --cwd packages/e2e --only  settings.open --watch --check-leaks --measure-after --measure instance-counts-difference-with-source-map --runs 197 &&
cat .vscode-memory-leak-finder-results/instance-counts-difference-with-source-map/settings.open.json

Additional Information

In addition to SettingsEditor2Input and Settings2EditorModel, the number of URI instances increases also by 197 which seems to be the URI from https://github.com/microsoft/vscode/blob/main/src/vs/workbench/services/preferences/common/preferencesEditorInput.ts#L24-L27:

export class SettingsEditor2Input extends EditorInput {
	readonly resource: URI = URI.from({
		scheme: Schemas.vscodeSettings,
		path: `settingseditor`
	});

The SettingsEditor2Input is created in https://github.com/microsoft/vscode/blob/main/src/vs/workbench/services/preferences/browser/preferencesService.ts#L108:

createSettingsEditor2Input(): SettingsEditor2Input {
	return new SettingsEditor2Input(this);
}

which then passed to the openEditor function:

	private async openSettings2(options: IOpenSettingsOptions): Promise<IEditorPane> {
		const input = this.createSettingsEditor2Input();
		options = {
			...options,
			focusSearch: true
		};
		await this.editorService.openEditor(input, validateSettingsEditorOptions(options), options.openToSide ? SIDE_GROUP : undefined);
		return this.editorGroupService.activeGroup.activeEditorPane!;
	}

[SimonSiefke]

Closing as fixed.