I’ve been a long time user of firefox and find that over time, starting firefox up takes a lot longer. Firefox uses sqlite as a database to store things like the list of places you’ve visited. Over time, these database files become fragmented, and need cleaning up. Here’s how to do it on mac OS X.
You should close Firefox, and then open up Terminal.app and type the following commands:
First, check the current size of your database files:
find ~/Library/Application\ Support/Firefox/Profiles -type f -name '*.sqlite' -exec ls -arlth {} \;
Next, vacuum and then re-index your database files. This may take some time – so don’t worry and leave it to finish.
find ~/Library/Application\ Support/Firefox/Profiles -type f -name '*.sqlite' -exec sqlite3 {} VACUUM \;
find ~/Library/Application\ Support/Firefox/Profiles -type f -name '*.sqlite' -exec sqlite3 {} REINDEX \;
Now check the sizes again:
find ~/Library/Application\ Support/Firefox/Profiles -type f -name '*.sqlite' -exec ls -arlth {} \;
You should see an instant speed increase.