src/vs/workbench/contrib/terminal/browser/terminalGroup.ts/TerminalGroup/dispose
class TerminalGroup:	override dispose(): void {
		super.dispose();
		if (this._container && this._groupElement) {
			this._container.removeChild(this._groupElement);
			this._groupElement = undefined;
		}
		this._terminalInstances = [];
		this._onInstancesChanged.fire();
	}