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Use the Mac OS dictionary vs. add on dictionary for spelling in Firefox


I have a series of questions related to the OS dictionary and about looking up the definitions of words and spelling. With Safari I could use Command+: to turn on Spell checker and loved using it. I have spell checker turned on with FireFox via Preferences/Advanced/Check my spelling as I type and like the other method better. I suppose I could get used to the method FireFox uses, but don't understand why cmd: can't work too. I even went in through system preferences and added it as a keyboard shortcut for Firefox without success. I dont' see anything in the pulldown menu's using that key-combination so what's blocking it? Another important feature that doesn't work is I can't click on a word to look up the definition. That's an important feature and I use it often. Because of these I stopped using firefox and continue using Safari even though Safari doesn't work for a main site I visit. Safari is also generally slow and locks up constantly causing me a lot of grief. If the problems I wrote about worked I wouldn't use Safari again and would commit to using Firefox. I would appreciate knowing how to do what I'm trying to do. Thanks,


Chosen solution

I'm running Firefox 20.0 on a MAC OSX 10.7.5. I've been using an Add-On called "Look Up In Dictionary" Works perfectly. It brings up the native MAC dictionary just as in Safari.

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Additional System Details

Installed Plug-ins

  • Gecko default plugin
  • Runs Java applets using the latest installed versions of Java. For more information: Java Embedding Plugin. Run version test: Java Information.
  • RealPlayer Plugin
  • iPhoto6
  • Allows webpages to support pressure-sensitive drawing on Wacom pen tablets.
  • The Flip4Mac WMV Plugin allows you to view Windows Media content using QuickTime.
  • Shockwave Flash 10.3 r183
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.


  • User Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv: Gecko/20111212 Firefox/3.6.25

More Information

When I followed the automatic steps above the following happened;
Troubleshooter.xpi (author not verified)
Incompatible Extension
Troubleshooter 1.0a could not be installed because it is not compatible with Firefox 3.6.25.

Tyler Downer
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1165 solutions 6639 answers

Please update to Firefox 16, which is the last version that will work with your computer, but it is still more modern than the version you are running.

Then Reset Firefox Reset Firefox – easily fix most problems

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10753 solutions 96760 answers

Question owner

Thanks for the suggestions. I installed firefox 16.0.2 and see additional features but still can't use the Mac dictionary or spell checker. I'm going to install the latest OS on this computer then I'll be able to install the latest version of firefox. The newest OS I can use on my other computer is 10.4.8 as it's a PowerBook and doesn't have an Intel CPU. Maybe I just can't do these commands.

How do I reset FireFox?

Modified by CGillesp

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10753 solutions 96760 answers

You can only use the Firefox spell checking dictionary in Firefox and not other dictionaries unless they are Hunspell compatible.
In case of the latter you would have to copy the dictionary files to the dictionaries folder in the Firefox application folder.

BigfootMac 2 solutions 1 answers

Chosen Solution

I'm running Firefox 20.0 on a MAC OSX 10.7.5. I've been using an Add-On called "Look Up In Dictionary" Works perfectly. It brings up the native MAC dictionary just as in Safari.

Question owner

Thanks for the solution BigfootMac.

Modified by CGillesp

OldRogue 0 solutions 2 answers

Opening the OS X Dictionary for a selected word anywhere is: Command+Option+D.

Open System Preferences > Keyboard > Keyboard Shortcuts. Select 'Services' in the left-hand pane, then scroll down to 'Searching' in the right-hand pane. Make sure the reveal arrow in pointed down, and 'Look Up in Dictionary' is checked.

Modified by OldRogue

Question owner

Thanks for the help OldRogue. I thought I had marked BigfootMacs suggestion as the answer, but I hadn't so I just marked it as the solution.