Dark mode email background

I use dark mode on my Mac all the time. (Mac Studio 2022 running Ventura 13.3).

I'm running MailMate Version 1.14 (5895)

In general I have no complaints with the use of MailMate in dark mode.

But emails from one source in particular are always hard to read. The problem seems to be that individual blocks of text appear with black backgrounds, but these dark blocks are surrounded by a sea of white (all within the email).

If I use another client, then the background also appears dark, making the blocks of text easier to read.