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All mails are shown in black and white.

Disabling the add-on again seemingly restores the coloring.

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Clarification

This behavior is not produced directly inflicted by the add-on.

The same behavior can also be re-produced by opening e.g. the Javascript Console, the Javascript Environment, Appointments or Reminders of the Lightning add-ons or other popup windows of other add-ons.

For all above cases it is irrelevant if the add-on Thunderbird Integration for Jira was installed or not respectively enabled or not.

but by a change in the Thundebird's own code.

It happened between Version 63 and 64; with all following versions showing this behaviour

The This behavior is controlled by the decorator of the main window of Thunderbird itself. As soon as loosing the focus a CSS rule is activated that has the described effect. You can click on the Thunderbird main window at any time, even when having popups opened to focus it again.

Related articles

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We will try to investigate further and attempt to fix this but since Thunderbird 73 probably needs a completely new Webextension this might not be fixed anymore.

Workaround

Please enable the column "Tag" in your mailfolder(s) to show the named labels:

Image Added

Gallery of different Versions

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