User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9pre) Gecko/2008052807 Minefield/3.0pre Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9pre) Gecko/2008052807 Minefield/3.0pre Currently when you open the bookmark dialog, with "bookmark this page" or editing the bookmark with the star button, bookmark is immediately saved. If you change folder or you cancel, the bookmark is re-saved by Firefox. This is a bit but useless HD stress. IMO it's better Fx save the bookmark when the dialog popup is closed. Reproducible: Always

this is by design

I know this, but why?

to unify code and behaviors between all bookmarks dialogs

Bug 451915 - move Firefox/Places bugs to Firefox/Bookmarks and History. Remove all bugspam from this move by filtering for the string "places-to-b-and-h". In Thunderbird 3.0b, you do that as follows: Tools | Message Filters Make sure the correct account is selected. Click "New" Conditions: Body contains places-to-b-and-h Change the action to "Delete Message". Select "Manually Run" from the dropdown at the top. Click OK. Select the filter in the list, make sure "Inbox" is selected at the bottom, and click "Run Now". This should delete all the bugspam. You can then delete the filter. Gerv