Add-ons
FreeCorrector – French & English Grammar Checker 1.4.0
by BenjiBurn
Free spell checker and grammar checker for your Thunderbird emails, in English and French. Underlines mistakes as you write and fixes them in one click. No AI, no account, works offline: your messages stay on your computer.
About this Add-on
FreeCorrector is a free spell checker and grammar checker for your emails, in English and French. It underlines your mistakes right in Thunderbird’s compose window, as you write; click the underlined word and it’s fixed.
• Only your own text is checked: not the quoted message, the "X wrote:" line or your signature.
• Free: no account, no subscription, no ads.
• No AI: your sentences are never rewritten, you choose every fix.
• 100% local: nothing is sent over the Internet, not even to a checking server. Works offline.
How it works
• Mistakes are underlined as you type: red for spelling, orange for grammar, blue for typography.
• Click an underlined word to see the recommended fix, with the other suggestions right below.
• A counter at the bottom right of the message shows how many mistakes there are. Click it for the full list.
• Works in HTML and plain text, for new messages, replies and forwards. The message you send contains exactly what you wrote, with nothing added.
English and French
The language is detected automatically sentence by sentence, so an email mixing both languages is checked in both. English: your/you’re, its/it’s, their/there/they’re, subject-verb agreement, tenses, “should of”, typos and more. French: agreement, conjugation, homophones, past participles, subjunctive, accents, capitals and punctuation.
Your messages stay yours
Everything is checked inside Thunderbird. FreeCorrector sends nothing over the Internet, collects no data and even works offline. Thunderbird itself blocks any network connection from the add-on.
Also
• Personal dictionary, with import and export.
• Picky mode for fine typography.
• A proofreader page (FreeCorrector button) to check a long text.
• A French verb conjugator: every tense of any French verb, from the FreeCorrector button or from the bubble of a conjugation mistake.
• Undo with Ctrl+Z after a fix.
Tip: to avoid double underlines, you can turn off Thunderbird’s own spell check as you type (Settings, Composition).
Open source
FreeCorrector is free software (GPL v3). It builds on two open-source engines, Harper for English and Grammalecte for French, and adds its own rules and context-aware ranking of suggestions. Also available for Firefox and Chrome, and as a Windows app. Source code: https://github.com/BenjiBurn/FreeCorrector
Made by BenjiBurn.
• Only your own text is checked: not the quoted message, the "X wrote:" line or your signature.
• Free: no account, no subscription, no ads.
• No AI: your sentences are never rewritten, you choose every fix.
• 100% local: nothing is sent over the Internet, not even to a checking server. Works offline.
How it works
• Mistakes are underlined as you type: red for spelling, orange for grammar, blue for typography.
• Click an underlined word to see the recommended fix, with the other suggestions right below.
• A counter at the bottom right of the message shows how many mistakes there are. Click it for the full list.
• Works in HTML and plain text, for new messages, replies and forwards. The message you send contains exactly what you wrote, with nothing added.
English and French
The language is detected automatically sentence by sentence, so an email mixing both languages is checked in both. English: your/you’re, its/it’s, their/there/they’re, subject-verb agreement, tenses, “should of”, typos and more. French: agreement, conjugation, homophones, past participles, subjunctive, accents, capitals and punctuation.
Your messages stay yours
Everything is checked inside Thunderbird. FreeCorrector sends nothing over the Internet, collects no data and even works offline. Thunderbird itself blocks any network connection from the add-on.
Also
• Personal dictionary, with import and export.
• Picky mode for fine typography.
• A proofreader page (FreeCorrector button) to check a long text.
• A French verb conjugator: every tense of any French verb, from the FreeCorrector button or from the bubble of a conjugation mistake.
• Undo with Ctrl+Z after a fix.
Tip: to avoid double underlines, you can turn off Thunderbird’s own spell check as you type (Settings, Composition).
Open source
FreeCorrector is free software (GPL v3). It builds on two open-source engines, Harper for English and Grammalecte for French, and adds its own rules and context-aware ranking of suggestions. Also available for Firefox and Chrome, and as a Windows app. Source code: https://github.com/BenjiBurn/FreeCorrector
Made by BenjiBurn.
