Mozilla Firefox ရဲ႕ URL မွာ about:config လို႔ရိုက္ထည့္လိုက္ရင္ Firefox ကိုစိတ္ႀကိဳက္ျပင္လို႔ရတယ္ဆိုတာ သိၿပီးသားျဖစ္ၾကမွာပါ။ ဘာလို႔ျပင္လို႔ရလဲဆိုေတာ့ Firefox ဟာ Open source ျဖစ္လို႔ပါပဲ။ အခုက်ြန္ေတာ္တို႔ ျပင္ၿပီးေတာ့ Firefox ကိုပိုအသံုးတည့္ေအာင္ လုပ္ၾကည့္ရေအာင္ဗ်ာ။

1) Disable Extension Compatibility Checks
extensions.checkCompatibility = False
extensions.checkUpdateSecurity = False

2) Location Bar (Set number Auto Complete URL at Address Bar)

This is a good hack to trim down that huge auto-complete list on your URL bar. By default it displays maximum 12 URL

browser.urlbar.maxRichResults = #

Enter Number at # (3,10,12 etc)

3) Stop Displaying Website Icon (Favicon) in Address bar & On Tab

browser.chrome.site_icons = False

4) Disable Prefetch (Helpful for frequent Google searcher, low-speed internet connection or low RAM)

network.prefetch-next = False

5) Extend Spell check to forms

layout.spellcheckDefault = 2
Change Value from 1 to 2

6) Disable Blinking Text

browser.blink_allowed = False

7) Speed Tweaks

network.http.pipelining false to true
network.http.pipelining.maxrequests 30 to 8
network.http.max-connections 30 to 96
network.http.max-connections-per-server 15 to 32
network.http.max-persistent-connections-per-server 6 to 8
network.http.pipelining.ssl false to true
network.http.proxy.pipelining false to true

8 ) Disable Annoying Browser Behavior

dom.disable_window_open_feature.menubar
dom.disable_window_move_resize
dom.disable_window_open_feature.titlebar
dom.disable_window_open_feature.toolbar

Set all of above to value False

9) Remove Tab Close Button from all Tab and set A single Close Button at Right
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browser.tabs.closeButtons = 3

Single Close Button to control all Firefox Opened Tabs. (value should be 3 and not 2 Thanks Andreas )

10) Disabler Browser Toolbar Tip

browser.chrome.toolbar_tips = False

11) Show More Tabs on Single Firefox Window before Scrolling

browser.tabs.tabMinWidth = 75

Setting lesser value with reduce Tab width

12) Past Copy Content with Middlemouse Click

middlemouse.paste = True

13) Scroll webpage in One Go

mousewheel.withaltkey.action=1

14) Disable Delay Time While Installing Firefox Add-on

security.dialog_enable_delay = 0

(Zero is number of seconds Firefox should wait while installing Add-on)

15) Increase History Undo Close Tab Limit ( Recently Closed Tabs )
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browser.sessionstore.max_tabs_undo=15

By default you can undo 10 recently closed tabs inorder to increase your history closed tabs. Change number 13 to as per your choice.

16) Open Firefox Default Search Bar Result in New Tab

browser.search.openintab=True

17) Right Click View Source in Your Favorite Editor

view_source.editor.external=True
view_source.editor.path= Path of Editor

(e.g. path C:\Program Files\npp.4.8.2.bin\notepad++.exe)

18) Enable/Disable Single Click to Select Whole URL in Address bar
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To Enable Single Click Select URL of address bar use the below about:config Tweak

browser.urlbar.clickSelectsAll = True

To disable Single Click Select

browser.urlbar.clickSelectsAll = False

19) Emule/ed2k link association (Linux users)

network.protocol-handler.app.ed2k= /usr/bin/ed2k
network.protocol-handler.external.ed2k = true

20) Fast Scrolling Across Tabs
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toolkit.scrollbox.scrollIncrement =75

( 75 is number of pixels to scroll at a time when scrolling the tab strip’s scrollbox. (Default: 20)

21) Auto Complete URL while You type at address Bar
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Many of above about:config hacks are available in Older Firefox Version, at the end if some thing goes wrong then feel free to restore your about:config to older setting see the below image of how to restore about:config
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