I can report that reseting of bookmarks settinngs is happening also for me.
But with diffrence that corrupted storage.js storage file is not created or somehow is cleaned before I find it.

This is same problem as @RustyTrombone reported. (will not speculate here what can be culprit, but FF routines is not excluded).

I really like the addon, and it's usefull.
This issue can be relly irritating for users with a lot of bookmarks.