I am using the new feature, spell checking with multiple languages, but this can only be set through the context menu which is lost. Please include these settings to be set in Preferences or the Add-on Dictionaries for permanence.
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I use LanguageTool extension, and supports the text check for multiple language (automatic language detection).
I noticed that this is implemented in Firefox 110.0. Firefox
Great job all around—this idea has been delivered!
Please note that it is not automatic...you have to use the context menu to turn on/off the spellchecker you want. And you can have multiple languages active.
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