Quick LOCK app screen with very Low Security like Child-Lock usage or prevent accidental showing of chat messages

### Your use case

#### What would you like to do?
A simple basic app lock-screen that prevents viewing notifications messages or app content viewing or sending. Low security equivalent to a Child-Lock etc.

#### Why would you like to do it?
To prevent clicking during a Remote ZOOM conference and accidently showing your chats, or a notification during meeting showing your message to ZOOM conf. users. Or preventing your kids from seeing or accidently sending messages to your chats.

See my posts and discussion in #3777 for more...

#### How would you like to achieve it?
There's many ways to do it, but basically anything that simply locks apps content and prevents viewing or typing into app. (Its ok if JS console hack can disable it.)

### Have you considered any alternatives?

Yea more secure methods were deemed too much work and too complicated due to Electron browser architecture, see posts and discussion in #3777

### Additional context

_No response_