Firefox's integrated spell checker is extremely handy for avoiding an embarrassing typo in an email, blog post or Twitter update, but after a while, the light red underline is easy to ignore. Fix that with a quick about:config tweak.
- Enter About:config in the Firefox address bar. If it pops up an alert, tell it that you know what you're doing and proceed.
- Search for ui.SpellCheckerUnderlineStyle. If you find anything, skip to step 5.
- If your system is like mine, you found nothing. That means you have to add this configuration value. Right-click the main portion of the window and select New > Integer.
- Now, enter ui.SpellCheckerUnderlineStyle to create a setting by this name.
- Now you can set the value of this setting to one of several options: 0 for no highlighting, 1 for a dotted line, 2 for long dots, 3 for a single straight line, 4 for a double underline (like you see above – that's my pick), and 5 for a squiggly line, which is the default.
I may be overly excited about this tweak since I edit typos from blog posts every day (everyone at Lifehacker HQ is getting a mandatory "do this" email), but if you're a Firefox user who hardly notices the light red underlines of the spell checker, it's definitely worth the adjustment. A nice side effect: Chances are you'll more actively add words to your custom dictionary as you go.
How to make spelling errors more visible in Firefox [Download Squad]