Sorry to bring back a really old thread, but it has screenshots which make the point perfectly and I wanted to share a fix - to double-check it's safe to do this.
If anyone else is getting the "annoying pop-up" experience to the XSS notification.
Just this, over and over and over:
Kkat wrote: ↑Fri Dec 08, 2017 4:06 pm

(picture borrowed from another thread)
I found the FAQ didn;t work because it doesn't match
Q: Can I turn off Anti-XSS activity notifications?
A: Yes, you can, just toggle the Noscript Options|Notifications|XSS preference.
So the option I've found that seems to work is this:
Click Advanced, and switch off the option “Ask confirmation for cross-site POST requests which could not be scanned”
This seems to stop the popups. But, is it safe? Advice welcome

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