It’s a simple process, and you only have to do it once.

snag the Firefoxmenuin the upper-right corner, then chooseOptions.

verify theGeneraltab is highlighted.

Options in Firefox for Windows

Select theCheck your spelling as you typecheck box under theLanguageheading in theLanguage and Appearancesection.

The change is saved automatically.

Go to theMenuicon in the upper-right corner of the Chrome web client and selectSettings.

A screenshot of Firefox settings with the General heading highlighted

Scroll to the bottom of theSettingsscreen and selectAdvanced.

In theLanguagessection, turn on theSpell checktoggle.

The changes are saved automatically.

A screenshot of Firefox settings with the Check your spelling as you type option highlighted

Go toEditon the Safari menu bar and selectSpelling and Grammar.

If you don’t seeEditas an option, select theSettings gearin the upper-right corner and chooseShow Menu Bar.

SelectCheck Spelling While Typing.

A screenshot of Chrome with the Settings command highlighted

Optionally, selectCheck Grammar With Spelling.

Can You Spell Check Yahoo Mail Messages?

Yahoo Mail doesn’t include a spell checker.

A screenshot of Chrome settings with the Advanced heading highlighted

When an error is found, the web app displays a red line beneath the problem word.

Spell check toggle in the Google Chrome Language settings

A screenshot of Safari’s Edit menu with the Spelling and Grammar heading highlighted

A screenshot of Safari with the Check Spelling and Grammar options highlighted