When I add an exception to NS 10.1.5.1 It only remembers it for the session. It doesn't get stored in storage-sync.sqlite as I can confirm with an sqlite viewer/editor on my linux system. When I restart the browser I see annoying xss popups, some times multiple of same kind such as having window.name in it, when I visit any of the affected pages.
The cookies saved by default for session, the data I clear on shutdown is like in screenshot below, dunno if it affects it.
Screenshot taken from my alt profile, running with LC_ALL=C in command line. Main profile has the same setting.
Unchecking Offline Website Data
doesn't help anything. Still getting warnings while visiting affected site after browser restart.
10.1.5.3 is still affected. It doesn't save XSS exception after restart either. Also if site triggers multiple XSS, dialog pops up even after closing the tab which is weird.
Fixed as of earlier version I didn't bother checking earlier, disregard this post.
Ubuntu 17.10 64 bits