Fix content-script overriding body css for every page

[rittme]

Fix the issue from #857.

The current content_script.css is overriding the body tag css properties for every page.

[rocramer]

Should be merged ASAP.

[Vinnl]

Just a heads-up that a non-broken update should now be available, so updating the extension should fix the issue from #857 for now: #857 (comment)

[privacytoolsIO]

Same issue, was very concerning since the text was changed to black on a dark gray background on our website https://www.privacytools.io/

[groovecoder]

Thanks @rittme for the contribution, and thanks everyone for the quick feedback on this. We will be more diligent about testing website compatibility in the future.

90K users received the buggy 2.3.3 version, and now 109K users are on the latest 2.3.4 (i.e., the rollback) version. 1.1M users are still on 2.3.2, but their next update should jump them straight to 2.3.4 instead of the buggy 2.3.3.

We are working on a full fix to include the security improvements, performance improvements, AND the bug-fix for the styling issue.

We merged #868 to fix the styling issue, if anyone here would like to help us spot-check that fix with the same sites that people saw this PR fix. Closing this PR for now.