Recently migrated to new laptop, backuped with FEBE. Bookmarks, History not saving anything since then
About a month ago I backed up my full profile and bookmarks from my old computer and restored/imported them into the new one using FEBE and the "Import and backup" tab, respectively. Both have the latest (18) version of Firefox. I followed all the steps to restore the old full profile into a new one, and then imported the bookmarks. So far so good.
At the beginning it was all fine, but about a week ago I realised I can't bookmark, nor see any history saved in the corresponding log windows. When I press Ctrl+D I don't get any window asking for confirmation to save the bookmark. When I try to make Firefox Show All History, I get a completely blank page. Nothing at all. I've tried disabling all the extensions to no avail. Still the same problem. I've tried closing and reopening Firefox, restarting the computer, same. I also checked the places.sqlite file, it's fine.
By the way, all the "Ctrl+Shift+B", "Ctrl+D", "Ctrl+Shift+H", "Ctrl+Shift+Del" options are in light grey, as if they had been disabled. On the contrary, the "Show All Bookmarks", "Bookmark This Page", "Show All History" and "Clear Recent History" ones are in black, as normal.
I've tried a few tentative solutions, none has worked so far. Please help. Thank you very much for any comments or observations.