It happens quite often that Firefox users tell me that their browser is not the fastest to start up. I personally do not have the problem at all, but this can be attributed to the solid state drive the browser is installed on, and the fact that I do not run excessive amounts of extensions or tabs that need to be restored on startup.
There are a few things that Firefox users can to do make Firefox start faster. There is the Firefox preloader application that loads on system start, the Firefox extension Bar Tab which loads tabs on demand and not all together on startup, cleaning the Firefox preferences file, the SpeedyFox software for Windows, or Vacuum Places add-on to optimize the SQLite databases used by the browser.
Long time Ghacks reader OAlexander just emailed me another tip to make Firefox start faster that I have not heard about before. He mentioned that he removed excess locales from his installed extensions and noticed that Firefox would start up noticeable faster.
Firefox extensions often come with multiple locales to provide users from all over the world with information in their own language. Most users usually only need one or maybe two of the locales. It appears however that all locales are loaded on startup when the extension is loaded (Can anyone confirm this?)
So, to make Firefox start up faster users would have to delete excess locales from Firefox extensions. An unzip software like 7-Zip is required for that operation. I explain how it is done with 7-Zip.
Make Firefox Start Faster
The first task is to locate the Firefox profile directory, which is the directory where the extensions are stored in. Firefox 3.6 and up users can click on Help > Troubleshoot Information to launch the file browser of the system with the profile folder as the selected folder.
Update: if you run a newer version of Firefox, type about:support in the address bar and hit enter. On the page that opens click on the folder button near the top to open the profile folder.
Before we start modifying anything we need to backup the extensions folder. This is just a precaution, but it is always better to have an option to restore a previous state.
Open the extensions folder and take a look around. Some extensions are stored in folders, while others are stored in .xpi files. The folders are basically unzipped xpi files, so no need to worry about the differences.
What you need to do now is to fire up your unzip software and navigate to the Firefox profile folder. 7-Zip users can copy the file path from the system file browser and paste it into the path field in 7-zip.
Make sure you close Firefox at this point, otherwise you will not be able to remove content from the extensions since they are in use when Firefox is open.
I suggest to work your way from top to bottom, starting with the xpi files and not the folders. Simple double-click on an xpi file to open its contents in 7-Zip. You will notice that they have a similar structure as the folders in the extensions root folder.
The path to the locales is always the same: Extension root folder > chrome > locale > filename.jar
Follow the path. Once the local folder is the root folder you may notice that multiple locales are provided by the Firefox add-on. You may now select all but the locales that you want to use. Press delete afterwards to delete them from the extension. Confirm that you want to delete the folders and files.
Now switch back to the extensions directory and repeat the process for all installed extensions. The folders are handled the same way.
Once all locale folders that are not needed have been removed it is time to start Firefox to see if the modification has made a difference. The effect depends largely on the installed extensions. Users with dozens of extensions may see a big decrease in startup time.
There is one problem though that needs to be mentioned. It is likely that extension updates will add the locale folders again to the extension. Which means that Firefox users need to delete the locale folders again whenever an extension gets updated.
Did you try this tip? What was the result on your system? Have another tip to speed up Firefox? Let everyone know in the comments.