Firefox is simply the best web browser. In my opinion, no other browser such as Opera, Internet Explorer, Chrome or Safari can beat Firefox. I’ve been using it for a very long time now and am very satisfied with it. However the only problem that I face with Firefox browser is it gets annoyingly slow after using it for a few months. Every morning when I launch Firefox and type a couple of letters in the URL location bar, it hangs for a while, then only it shows a bunch of suggested links. Even when I close Firefox, it takes a while for the firefox.exe process to be terminated.
I figured that since Firefox hangs when I am typing in the URL, it could probably be that I have a huge list of history. My Firefox 3 has all the default configurations and I never change anything. By default Firefox remembers my browsing history for 90 days which means that Firefox will remember the URL of the site that I visited for the past 3 months. So I did a little investigation on my Firefox history list to check if it is the culprit that causes my Firefox to respond slowly.
I downloaded a free tool called MozillaHistoryView which reads the history data file of Firefox Web browser, and displays the list of all visited Web pages in the last day. Again it took quite a while for MozillaHistoryView to load the history file and I was shocked to see that I have 72184 links in my Firefox history! If you divide 72184 with 90 days, I visit an average of 800 websites a day, 33 every hour! Beat that and you’ll be the next raymond.cc 
(I’m just joking)
My idea of fixing this Firefox slow respond problem is to export all the history into a text file so I can search for it at a later time when I need it and then delete the Firefox history file to start all over again. Starting in Firefox 3, both the bookmarks and browsing history are stored in the places.sqlite file, located in the Firefox profile folder. Since the bookmark is also saved in the same file as history, I will need to backup my bookmarks as well. When I am done with that, I will try lowering down the number of days from 90 days to 45 days for Firefox to remember my browsing history.
Backup Firefox Bookmarks
1. Click Bookmarks from the menu bar and select Organize Bookmarks.
2. Click the Import and Backup button and select Backup.
3. Save the bookmark backup .json file to a location that you remember on your hard drive.
Export Firefox Browsing History
1. Download MozillaHistoryView and run it.
2. You can either export it to text or HTML format. For HTML format, go to View and select “HTML Report – All Items”. For text file, go to Edit and click on Select All. Then go to File and select Save Selected Items.
Delete Firefox Browsing History File (places.sqlite)
1. Make sure that Firefox is not running
2. Go to RUN, type %appdata%/Mozilla/Firefox/Profiles/ and hit Enter.
3. You should see a folder with random letters and numbers followed by a .default (eg; 89ns5tbp.default)
4. Go in to the folder and rename the places.sqlite file to places.sqlite.bak
Note: I noticed that clearing the “Browsing History” from Firefox doesn’t make the size of places.sqlite file smaller. That’s why I resort to letting Firefox re-create a new places.sqlite file.
Run Firefox now and you should notice that Firefox no longer slow or hangs. To restore your bookmarks, go to Bookmarks in your menu bar and select Organize Bookmarks. Then click the Import and Backup button > Restore > Choose File. Select the file that your backed up earlier.
Lower Firefox History Size
1. Go to Tools > Options..
2. Click on the Privacy button and click on the drop down menu for Remember History. Select “Use custom settings for history”.
3. Set the “Remember my browsing history for at least XX days” to 45 and click OK.
