Grammar and Spell Checker — LanguageTool

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wót Guido3 dnja Jan. 20, 2023 · trajny wótkaz

Does work well in Firefox but not in Thunderbird. Extension is installed. I see a LanguageTool-Button in every E-Mail window next to the Attachments-Button, where I can access the Settings for LanguageTool. But it does not mark any errors in the text, does nothing

Thunderbird 102.7.0 on Windows 10
LanguageTool 6.0.5

@Christopher Blum: I've tried that already. I have just one other add-on (Provider for Google Calendar) and deactivation does not solve the problem. You can find a screenshot here:
postimg.cc/2bzPDTDw