Email, Messaging, & Video Calls Email How to Spellcheck as You Type in Mozilla Thunderbird Correct those typos and embarrassing spelling errors by Heinz Tschabitscher Writer A former freelance contributor who has reviewed hundreds of email programs and services since 1997. our editorial process Heinz Tschabitscher Updated on September 11, 2020 Email Yahoo! Mail Gmail Tweet Share Email Typos, like mistakes, are natural. As your fingers hurry over a keyboard, you can sometimes hurry too fast and too far. Other times, it's merely a matter of not knowing how to spell a word. Use the Mozilla Thunderbird spellchecker to catch and correct typos and spelling errors. With inline spell checking, you can correct errors immediately as you type. Check Your Spelling as You Type in Mozilla Thunderbird To have Mozilla Thunderbird check the spelling in emails as you write them: Go to the Thunderbird menu and select Preferences. Select the Composition tab. Under Spelling, select the Enable spellcheck as you type check box. To change the spellcheck dictionary, select the Language drop-down menu, and choose an option. While composing an email, you can turn the inline spellchecker on or off by selecting Options > Spellcheck As You Type from the menu.