The bug
Removing pop-up using Tab key doesn't move you automatically to other pop-up, so you need to click on Tab again to move to the other pop-up.
How to reproduce
Open the Launcher, and navigate to the Settings page
Toggle "Use beta version of the Launcher" option a few times (a pop-up should appear each time this is done)
Use the Tab key to select an X in one of the pop-ups
Press Enter
❌ The next pop-up is not automatically selected
Closing the ticket as this functionality of the Launcher "Works as intended".