The title pretty much says it all: I cannot load temporary addons anymore. They show up on the “about:debugging” page after I try to load them, but do not show any signs of running. The “Inspect” button shows an error “Can’t find profile directory” with the filename XULStore.jsm.
I’ve tried creating deleting (renaming) XULStore.jsm, restarting Firefox, creating a new profile, and rebooting the computer. Still having the issue.
One thing that may be related is that I was working on a very memory intensive addon (it attempted to load 300+ multi-megabyte images) when this started. However, it is not just this addon that I cannot temporarily load; others that worked before will not load as temporary addons.
But:
This error only occurs after setting
Edit → Preferences → Privacy & Security → History → Never remember history
(which Firefox automatically changes to “Use custom settings for history → Always use private browsing mode” after restarting)
I keep discovering bugs like this in Firefox.
It’s the gift that keeps giving!
If you’re unsure that it is the same bug, report a new bug. It’s better to have duplicates than no info…
If you are fairly certain that it’s the same thing, post a comment on there.