Very Slow Firefox Start-up with Missing Bookmarks Due to Other Use

From Windows 11 start Firefox v 142.0.1 opens with an entirely blank page - toolbars, graphics, webpage - everything taking over a minute to load up with toolbars and then a further 2 minutes to load www.theguardian.com/uk. Firefox then frequently crashes and on re-start the bookmarks toolbar is empty - yes it is visible. I have been renaming places.sqlite to places.sqlite.old every few days since 27 Aug. The Manage Bookmarks - Library shows all bookmarks when Firefox is behaving but is completely empty when the bookmark toolbar is also empty. Restarting Firefox does not reinstall the bookmarks. The only solution is to restart Windows 11. Any ideas on speeding up and preventing this bookmark problem. Thanks