no colored diffs in windows dark mode

I use windows 10 in high contrast dark mode. I use chrome for code collaborator version 13.0.13002. I use the "high contrast" add-on to get chrome to reverse the colors of its content, resulting in most page being white text on a black background. So in code collaborator, I would see the highlighted differences in the files in reverse colors. Which was perfectly fine.

But chrome has made some change recently where it is natively aware of windows dark mode and I no longer need the "high contrast" add-on. Chrome reverses the colors -- except *not* in code collaborator. Instead, it just reverses the text (shows white on black) for everything and somehow loses the colored difference highlighting. Reviewing code has become a horrible scan along the line numbers to find the changes the developer has made.

I have tried using settings -> display -> select webUI theme -> dark to no effect. I tried classic too. I have similar issue in firefox and edge -- no colors in the file diff view. I also tried telling chrome not to go into dark mode ("--disable-features=DarkMode") but that doesn't seem to have any effect on chrome at all. Same with a couple of dark-related settings in chrome://flags/ to no or ill effect.

Aside from abandoning windows dark mode (which is not a reasonable solution given my degraded eyesight), is there anything I can do to get the colored difference highlighting back in code collaborator under any windows browser?