Add warning for when the user tries to add extensions to tor browser for android and desktop

💡 Proposal

Extensions, aside from NoScript, are not recommended for tor browser due to privacy and security concerns. They make the user more fingerprintable and the integrity of the 3rd party applications cannot be verified and may compromise the users privacy/security. As of writing this in May 2024, there are no warnings in the app for either android or desktop telling the user this. I propose adding a popup with a blurb explaining this to the user.

Security, Privacy, and Accessibility Implications

Informing the user that they may be compromising privacy or security by installing 3rd party extensions helps them make a better decision to install the extension or not (like if they are using tor browser mainly for anti censorship, they may install it anyways as it likely does not interfere with that), or to take other measures instead (such as dimming the screen or turning on a blue light filter instead of installing the extension Dark Reader to reduce eye strain or accommodate visual sensory needs).

Other Trade-Offs

People don't like pop-ups generally and may just click through it.

---