1) More screen space.

2) Smart keywords.

3) Keyboard shortcuts.

• Spacebar (page down)
• Shift-Spacebar (page up)
• Ctrl+F (find)
• Alt-N (find next)
• Ctrl+D (bookmark page)
• Ctrl+T (new tab)
• Ctrl+K (go to search box)
• Ctrl+L (go to address bar)
• Ctrl+= (increase text size)
• Ctrl+- (decrease text size)
• Ctrl-W (close tab)
• F5 (reload)
• Alt-Home (go to home page)

4) Auto-complete.

5) Tab navigation.

• Ctrl+Tab (rotate forward among tabs)
• Ctrl+Shft+Tab (rotate to the previous tab)
• Ctrl+1-9 (choose a number to jump to a specific tab)

6) Mouse shortcuts.

• Middle click on link (opens in new tab)
• Shift-scroll down (previous page)
• Shift-scroll up (next page)
• Ctrl-scroll up (decrease text size)
• Ctrl-scroll down (increase text size)
• Middle click on a tab (closes tab)

7) Delete items from address bar history.

8) User chrome.

9) Create a user.js file.

10) about:config.

11) Add a keyword for a bookmark. .

12) Speed up Firefox.

• Type “about:config” into the address bar and hit return. Type “network.http” in the filter field, and change the following settings (double-click on them to change them):
• Set “network.http.pipelining” to “true”
• Set “network.http.proxy.pipelining” to “true”
• Set “network.http.pipelining.maxrequests” to a number like 30. This will allow it to make 30 requests at once.
• Also, right-click anywhere and select New-> Integer. Name it “nglayout.initialpaint.delay” and set its value to “0″. This value is the amount of time the browser waits before it acts on information it receives.

13) Limit RAM usage.

14) Reduce RAM usage further for when Firefox is minimized.

15) Move or remove the close tab button.

• 0: Display a close button on the active tab only
• 1:(Default) Display close buttons on all tabs
• 2:Don’t display any close buttons
• 3:Display a single close button at the end of the tab bar (Firefox 1.x behavior)

Source: lifehack

Source: computer world

·Spacebar (page down)
·Shift-Spacebar (page up)
·Ctrl+F (find)
·Alt-N (find next)
·Ctrl+D (bookmark page)
·Ctrl+T (new tab)
·Ctrl+K (go to search box)
·Ctrl+L (go to address bar)
·Ctrl+= (increase text size)
·Ctrl+- (decrease text size)
·Ctrl-W (close tab)
·F5 (reload)
·Alt-Home (go to home page)” 

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