"Color All Plaintext Messages" doesn't seem to work right

[powerjungle]

When I open most messages, it works fine. But I noticed some emails from the linux kernel mailing list, where it doesn't apply any style. Here are two emails from lore.kernel.org where this happens: email-1 and email-2.

The style I've chosen is with a dark background, but the email opens up with a light background and no colors.

I can't seem to find any pattern in the email text that makes these two special, but every time I open these specific emails and some others it has no style.

EDIT: Also about the first email, when I disable the option it still doesn't change the style, when it should've, because this is a git diff. So the issue might not be specific to this option. Of course I forgot to mention I'm running Thunderbird 91.11.0.