Firefox has a really useful built-in dictionary that underlines a misspelled word, so you can see at a glance whenever you have typed something wrong.

But you might have noticed that when you type a wrong word into the email subject (in Gmail for example) or any single line element, it doesn’t work.

Yes, the default setting corrects and spell checks all multiple lines areas, leaving it to you to find errors in single lines box such as titles, subjects, tags…

Here are some quick steps to set Firefox to check every field:

1. Type about:config in the address bar and look for ‘layout.spellcheckDefault’.
2. The default value is 1, which means that Firefox will spell check all “textarea” fields, but changing it to 2 will make it check all fields of any kind.

You can also deactivate the spell checker function by setting the value to 0, but I suggest you keep this function on as it doesn’t really bother, but can really help you out with distraction errors and mistakes.