Its like every technological complexity that isnt immediately self fixing and easy is my fault.

"..Sure", .. I said...

I wasnt actually sure.

I thought it might be syncing my bookmarks to mobile me at first but it wasn't that. Mobile me bookmark sync was disabled in System Preferences. So something else was going on. I couldnt remember, so I started to search. Soon found it and it reminded me of just how much we keep forgetting as our systems become more and more complex and our settings become more and more hidden.

To fix Bookmarks Not Saving in Firefox

Enter about:config in the location bar in Firefox. about: is an internal URL to the browser and can yeild surprising things. about:config gives you access to the Firefox preferences editor in raw form. You can change many things, but be careful. Its a bit like using Regedit on Windows - you can make a mess. Firefox issues a suitable warning. Click 'Ill be careful, I promise' to continue.

 Firefox editor

To actually fix your bookmark not saving, type 'browser.places' to narrow the filter of a million settings.

Now we are narrowed down to the ones we are interested in, and can right click (ctrl-click on a mac) and select 'reset' from the pop up menu for each item in the list which is set to a status of 'user set'

Bingo - you'll now be able to save your bookmarks and have a quieter life again.