Quit saving session
Restart, loading saved session
Results:
moz-extension://af7e49b9-68ab-4fb8-b15c-178d2196beae/ui/options.html#;tab-main-tabs=1 opens, but Per-Site Permissions does not load (does not display any site names), instead only a spinner spins (which is good, because otherwise what would be the point in a spinner
).