We show you three different ways to enable or disable the spell checking feature that checks your spelling in web forms in Mozilla Firefox.
Option 1 – Basic Firefox Menu
- Select the “Menu”
button located at the upper-right corner of the screen, then choose “Options“.
- Scroll to the “Language & Appearance” section.
- Select “Check my spelling as I type” if you want to turn spell checker on. Uncheck it if you wish to have it off.
Option 2 – From about:config
- Type “about:config” in the address bar.
- In the filter field type “spell“.
- Find the entry for “layout.spellcheckDefault” and double-click it.
- Set the integer to “1” to “enable”the spell checker. Set the integer to “0” to “disable“the spell checker.
Option 3 – Via prefs.js file
- Close Firefox.
- Navigate to the following location based on your operating system.
- Windows 10/7/8 – “%APPDATA%\Mozilla\Firefox“
- Unix/Linux – “~/.mozilla/Firefox“
- Mac OS X – “~/Library/Mozilla/Firefox” or “~/Library/Application Support/“
- Open the “Profiles” folder.
- Open the folder that represents the profile you would like to edit. The name of the folder will vary. It is usually a bunch of characters, followed by “.default”.
- Open the prefs.js file with a text editor like Notepad.
- Look for a line that contains “layout.spellcheckDefault“. If it doesn’t exist, add a line for it in the file and set it as desired using these examples:
- user_pref(“layout.spellcheckDefault“, 1); = Spell Check enabled
- user_pref(“layout.spellcheckDefault“, 0); = Spell Check disabled
Paul says
After exhausting all the other methods listed here and elsewhere this is how I solved it on my PC running windows 10 and Firefox version 108.0.1 (64 bit) I hope this helps. My problem was a missing Prefs.js file within a folder…..
To find a profile folder in the default location on Windows:
Press “Windows key Windows Key.png + R” to open the Run box
(or, you can click “Start → Run…” on Windows 2000/XP)
In the Run box, type in %APPDATA%
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I got to the AppData folder and noticed that there were folders named Local and Roaming I clicked roaming – Mozilla – Firefox – Profiles and then a file with some characters a dot and the word default mine looked like this: 3g2fmz2t.default I clicked on this and there were three files but most importantly one called prefs.js I right clicked on it selected edit and noticed that there was an entry like this: user_pref(“layout.spellcheckDefault”, 1); it was initially set to 0, so I changed it to 1 and saved the file. I then copied the prefs.js file (do not use move or use cut) and navigated back to the AppData folder and then selected the folder named ‘local’ then clicked on mozilla – firefox – profiles, and another file named the same as before 3g2fmz2t.default I clicked on it and the folder was empty I then pasted the prefs.js file we copied a little earlier and restarted firefox and I got my spell check to work again.
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Greta says
Only thing that worked for me was adding the British English Dictionary. For anyone still trying to do this, you can just go ahead and try this first:
1. Go to top right hand side menu
2. click “Settings”
3. Go to bottom left “Extensions and Themes”
4. Go to the “Dictionaries” tab and choose the language you prefer (for me it was British English, but there’s a US version, Australian version, etc.)
Good luck!
Sayeed bin miraj says
Yes its help me.
Zee-Zee says
See my post of 18 March 2020 for a description of the problem.
Thanks Don, for saying these options no longer work.
Since 18 March, in fact yesterday evening, I got a technical friend to try option 3 above as I had not managed that myself.
He got as far as step 4 in option 3 above. There were 2 folders with charaters and default in the title. They both had various sub folders but none of them or their subfolders had a file called prefs.js. He spent about an hour trying various things, and nothing has re-enabled the spell checker.
So I have decided to give up on firefox, uninstall it and use a different browser. I can’t be doing with an internet browser that you need to be a geek to make the spell checker work.
Zee-Zee says
Firefox used to be checking my spelling in gmail, underlineing wrong words with a red wavy line. but firefox noticed it was working slowly and said I could do something to speed it up, which I did. (sorry I did not write down what exactly it was).
Now the spell checking is not working.
I have checked option 1 above using the Basic Firefox Menu, and check spelling as you type is ticked. I checked option 2 From about:config above and it was set to 1 not 0. I got a bit lost trying option 3 above. other comments above say you need to download a dictionary but as it was spell checking before, that should already be there. And none of the other comments above have worked either.
don says
these options no longer work
David says
Nope, It just suddenly doesn’t work. I’ve been sing the internet, almost daily for 20+ years, so I’m no novice, but on acquiring a new PC, Firefox no longer underlines spelling errors on any message application (e.g., Yahoo, Facebook, etc)
The spellchecking box (“Check your spelling as you type”) IS ticked. in Option – Tools – Language and yet it still doesn’t work (I have also downloaded the English dictionary add-on).
john says
There is no option for spell check anywhere under options /language why are you saying there is. There is no spell check and nothing even close. I will never use this again
JoeHx says
Setting “layout.spellcheckDefault” to 2 enables spell check for all text boxes. Super useful!
David C. Burdick says
1. Select the “Menu” button located at the upper-right corner of the screen, then choose “Options“.
2.. Scroll to the “Language & Appearance” section.
3. Select “Check my spelling as I type” if you want to turn spell checker on. Uncheck it if you wish to have it off.
May 8, 2019
SHOULD READ:
1. Select the “Menu” button located at the upper-right corner of the screen, then choose “Options“.
2.. Scroll to the “Language & Appearance” section.
3. Under ”Language and Appearance” see ”Language.”
4. Select “Check my spelling as I type” if you want to turn spell checker on. Uncheck it if you wish to have it off.
for ABSOLUTE ACCURACY to direct the questioner.
dCb
Jennifer Ayres says
I have opposite problem I turned off spellcheck in options but it stays on. the pref.js file has no setting for spell check. This is also happening with Chrome. Red squiggly lines very annoying.
Wizlon67 says
Go to add ons and add the dictionary for whichever language that you want then restart firefox.
Andrei says
Same issue with Gmail. Only happened after I finally updated Firefox due to my addons being disabled as they couldn’t be checked bug.
Joe Lavery says
I recently chaged to a new PC and installed Firefiox as usual, but the spellchecker does not work.
I have tried all of the solutions offered here but it remains off.
While tyoing this message I just added a new dictionery and it now works.. :o)
julie says
I’ve tried all three and my spell check still doesn’t work within Gmail.