Firefox is a free and open-source web browser developed by the Mozilla Foundation. Firefox uses the Gecko layout engine to render web pages, which implements current and anticipated web standards.
1. Click on the Address Bar
It’s the same area where you type a website or search query.
2. Visit Advanced Preferences
Type in about:config in the address bar to open Advanced Preferences option in Firefox. Unfortunately, firefox doesn’t allow advance settings to be edited in the setting menu.
3. Accept the Warning!
Access the warning and click on Accept the Risk and Continue. about:config opens up advance options to customize Firefox. Be cautious when editing anything in there.
If it shows true, it’s already enabled. You do not need to change any setting.