Add a way to inject user stylesheet rules

[jspenguin2017]

I don't want to break the DOM Inspector, but user stylesheet is sometimes required.

See also:
MajkiIT/polish-ads-filter#12101

[hawkeye116477]

Also GDPR can't be hidden on https://sportowefakty.wp.pl without userCSS, cuz it has inline style with overflow: hidden !important.

[jspenguin2017]

This issue is non-trivial. I recommend you to create an Userscript to remove the inline styles.

I'll add non-annoyance rules to Nano Defender for now.

[hawkeye116477]

Ok, I was rather hoping to solve this problem in Nano Adblocker. Anyway currently we have another solution in our special extension, we just search for button with specific text and click on it 😄.

[jspenguin2017]

What I probably will do is to add a new compiler directive (!#nano-use-usercss?), which will force the next rule to become injected via UserCSS.

Things to consider:

• Extend current system or roll a small secondary system? Not sure for how long will this be needed.
• How to handle exception rules?
• How to handle !#if, !#include, and other directives? Need to test to make sure they don't conflict.