Disable HTML 5 Video Autoplay
By default, Firefox plays HTML 5 videos once they're loaded in a page, which is particularly annoying. To turn this off, do the following:
- Type about:config in the browser's address bar and hit enter.
- Confirm that you will be careful if the notification comes up.
- In the Search: box, type media.autoplay.enabled to filter to the setting.
- Double-click the setting so that its Value column reads false.
- Close the about:config tab.
Search Engines Removed
The Firefox search engines can be customized by going into Options -> Search. However, one day I discovered that all my search engines had been deleted, I couldn't add new ones, and the button to "Restore Default Search Engines" was disabled. This appeared to have been caused by a bug in a Firefox upgrade. To fix the problem, I did the following:
- In the menu, click Help, then Troubleshooting Information.
- In the section Application Basics, next to Profile Folder, click Open Folder.
- Find the file search.json and delete the file or rename it.
- Close Firefox and re-open it. The file should be recreated with its default settings and you should have the ability to change your default search engine again.
Won't Prompt to Remembers Passwords
Click Tools, choose Options. Under the Privacy tab, in the History frame, under Always use private browsing mode, make sure that Remember search and form history is turned on.
Won't Stay Logged In
Click Tools, choose Options. Under the Privacy tab, in the History frame, click the Settings button next to Clear history when Firefox closes. Make sure "Active Logins" and "Cookies" are unchecked in the History frame.