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Thunderbird 78.x and Windows 10: cannot enable the Dark/Light mode from the Thunderbird settings within the standard profile .

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  • 1 has this problem
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  • Last reply by sr

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Opening the Add-ons Manager, Preferences, Extensions & Themes I have the standard mode enabled. Activation of the Dark and/or Light themes however shows no effect .

Note: Changing Windows setting and selecting in Windows the dark mode for Apps, then Thunderbird turns into a dark layout. But, also in this set up, under the Add-ons Manager of Thunderbird , the standard mode remains the only mode to be active. Dark and Light mode are shown but cannot be enabled in Thunderbird.

I have now created a second Thunderbird profile. In this new profile the dark and light mode can be enabled by Thunderbird. In the standard profile (the old one) however the problem remains.

Question: is any specific file which I could copy from the new profile and paste it in the old profile to restore the Dark/Light theme functionality also for this old profile?

Opening the Add-ons Manager, Preferences, Extensions & Themes I have the standard mode enabled. Activation of the Dark and/or Light themes however shows no effect . Note: Changing Windows setting and selecting in Windows the dark mode for Apps, then Thunderbird turns into a dark layout. But, also in this set up, under the Add-ons Manager of Thunderbird , the standard mode remains the only mode to be active. Dark and Light mode are shown but cannot be enabled in Thunderbird. I have now created a second Thunderbird profile. In this new profile the dark and light mode can be enabled by Thunderbird. In the standard profile (the old one) however the problem remains. '''Question''': is any specific file which I could copy from the new profile and paste it in the old profile to restore the Dark/Light theme functionality also for this old profile?

Modified by sr

Chosen solution

I did not get any reply from other users, so I solved the problem by myself. Creating a new profile, the Dark and Light themes of Thunderbird could be normally activated and deactivated in the new profile. I than decided to use this new profile as standard, copying the emal files of the old profile into the new profile. Even if they were big files, it has worked. In this way I did not loose information .

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Chosen Solution

I did not get any reply from other users, so I solved the problem by myself. Creating a new profile, the Dark and Light themes of Thunderbird could be normally activated and deactivated in the new profile. I than decided to use this new profile as standard, copying the emal files of the old profile into the new profile. Even if they were big files, it has worked. In this way I did not loose information .

Modified by sr