If you cannot switch from the unresponsive app, press Command + Option + Shift + Esc for three seconds to force it to quit. This key combination tells macOS to force quit the front-most app.Alternatively, if you are using Safari or any other browser, you can disconnect your Internet, then open the web browser, navigate from the malicious web page, then reconnect to the Internet.
Some counterfeit and third party power adapters and batteries may not be designed properly and could result in safety issues. To ensure you receive a genuine Apple battery during a battery replacement, we recommend visiting an Apple Store or Apple Authorized Service Provider. If you need a replacement adapter to charge your Apple device, we recommend getting an Apple power adapter.