Unpinned threads

This has happen several times but I come into the site and all or most of my threads have been unpinned.
Why is this happening and what solutions are there?

Threads that get deleted or archived don't appear in the catalog.

Either that or you have some addon that clears your local storage periodically.

I don't think it's an add on other wise I will lose stuff on other sites too.
I remember I had FF set up to delete cookies when they expire, maybe that plays into this?

>>3
>I remember I had FF set up to delete cookies when they expire, maybe that plays into this?
Probably.
Something is deleting local storage in any case.