The Mozilla Firefox Cheat Sheet is a great way to learn more about the firefox browser. New users will find this one page firefox reference useful because it lists all those little tips and workarounds that speed up your firefox workflow.
The Cheat Sheet has three major sections. Section one deals with firefox shortcuts (general, navigation, text, search and mouse shortcuts). Section two lists the important locations like cache and profiles and section three lists some neat tips and tricks like blocking popups and customize toolbars. You might even learn something new if you are working with firefox on a daily basis, try it out.
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It’s worth to mention that if you are using Firefox under Linux with KDE the CTRL+Tab is mapped to KDE desktop switcher and it overrides Firefox’s Next Tab and Previous Tab shortcuts.