Quotes and monospace text unreadable in email with dark theme

I primarily read Fedora Discussion through email notifications.
I have dark theme set in all my devices, and my email clients respect that.
I use Thunderbird on desktop and the default /e/ OS Mail app (a fork of K-9 Mail) on mobile.
Unfortunately, for HTML mail, quotes and monospace text are unreadable,
because they are shown as white text on white background.
It look like the background color for these formatting types is hardcoded to white in the email itself,
while the device’s dark theme sets foreground text color to white also.

My workaround is to select the white rectangle if I need to read its content.
The selection color scheme is light blue-on-white, so the text is (just barely) readable.
Could the email theming be adjusted so that HTML email displays nicely also when dark theme is used?

An example of white-on-white quote (Thunderbird on Windows):

An example of white-on-white verbatim text (Thunderbird on Windows):

Thanks for the report. There’s a template for this which I can update.

So, it turns out that this is a Thunderbird bug. Some related reports:

It turns out there’s an HTML feature to detect dark mode, and Discourse email uses this. Some mail clients implement this — see Can I email… @media (prefers-color-scheme) — while others implement a “dark mode” by inverting colors, ignoring the styling in the message.

Thunderbird, however, half implements this: enabling dark mode, but not picking up the right color scheme. There’s not much Discourse can do about this without breaking it for the clients that do the right thing.

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Thank you for investigating this.
That indeed seems to be the case.
While I wait for Thunderbird to gain support for that CSS feature,
I worked around the issue by overriding colors at
PreferencesGeneralLanguage and AppearanceColors…

I still have to figure out if and how I can make Discourse email readable in my mobile client.