src/vs/workbench/contrib/snippets/browser/tabCompletion.ts/TabCompletionController/_update
class TabCompletionController:	private _update(): void {
		const enabled = this._editor.getOption(EditorOption.tabCompletion) === 'onlySnippets';
		if (this._enabled !== enabled) {
			this._enabled = enabled;
			if (!this._enabled) {
				this._selectionListener?.dispose();
			} else {
				this._selectionListener = this._editor.onDidChangeCursorSelection(e => this._updateSnippets());
				if (this._editor.getModel()) {
					this._updateSnippets();
				}
			}
		}
	}