Thunderbird version 1.0+ (20050626) When you use the spell-check dialog, and you change the language, you have the option to recheck the entire page. this is handy is you keep switching between differetn languages, and you started to type a message in a different language than the default (the spell checker suddenly started to complain about almost every word). But when you use spell-as-you-type, and you notice that almost every word is flagged as incorrect, you can change the language in the Options or the Spell-Check dialog. But when you changed the language, the page isn't rechecked, and you notice that the words stay flagged as incorrect. For example (assuming that you have installed English and Dutch dictionaries): - switch on spell-as-you-type - set the language to English - type "dit is een test" (Dutch for "this is a test") - notice that 3 words out of 4 are incorrect - open the spell-check dialog and change the language to Dutch - notice that the words stay flagged Work around : - switch off spell-as-you-type - switch it back on See also bug 69687.

The solution would be quite easy, just call InlineSpellChecker.checkDocument again when the language is checked : function RefreshInlineSpellChecker(target) { if (InlineSpellChecker.inlineSpellChecker) { if (InlineSpellChecker.inlineSpellChecker.enableRealTimeSpell) InlineSpellChecker.checkDocument(window.content.document); } } (similar to ToggleInlineSpellChecker in mail/components/compose/content/MsgComposeCommands.js)

*** This bug has been marked as a duplicate of 305020 ***