One of the workstations at work had suddenly decided to not record any history of new sites visited .. and not to show any traces of old visits. After a bit of searching I found the recipe for How to fix a corrupt localstore which mentions a few of the same symptoms, in particular that the bookmark dialog won’t show up. Stopping Firefox and then renaming localstore.rdf did however not solve anything. Luckily I had remember that somewhere someone mentioned the places.sqlite database as containing information for the location field, so after stopping Firefox again, deleting the places.sqlite file and then restarting Firefox, everything went back to normal. Yet again Firefox knows where it has been!