src/vs/workbench/services/hover/browser/hoverService.ts/HoverService/_keyUp
class HoverService:	private _keyUp(e: KeyboardEvent, hover: HoverWidget) {
		if (e.key === 'Alt') {
			hover.isLocked = false;
			// Hide if alt is released while the mouse os not over hover/target
			if (!hover.isMouseIn) {
				this.hideHover();
				this._lastFocusedElementBeforeOpen?.focus();
			}
		}
	}