src/vs/workbench/browser/parts/compositeBar.ts/CompositeBar/activateComposite
class CompositeBar:	activateComposite(id: string): void {
		const previousActiveItem = this.model.activeItem;
		if (this.model.activate(id)) {
			// Update if current composite is neither visible nor pinned
			// or previous active composite is not pinned
			if (this.visibleComposites.indexOf(id) === - 1 || (!!this.model.activeItem && !this.model.activeItem.pinned) || (previousActiveItem && !previousActiveItem.pinned)) {
				this.updateCompositeSwitcher();
			}
		}
	}