Steps to replicate the issue (include links if applicable):

• Goto https://de.wikipedia.org/wiki/Tschernjachowsk
• if you use a different skin, set your skin to Vector 2022 (Preferences->Appearance)
• enable "Accessibility for Reading (Vector 2022)" (Preferences->Beta Features)
• Switch to dark mode (Color->Dark in the toolbox on the right side)

What happens?:

• Dark text on dark background in the infobox

What should have happened instead?:

• Text should be in readable color.

The problem seems to be the combination of CSS rules

html.skin-theme-clientpref-night .infobox td:not(.notheme),
[...] {
 background:inherit !important;
 color:inherit !important;
 border-color:var(--border-color-subtle,#c8ccd1) !important
}

and

html.skin-theme-clientpref-night .mw-parser-output [style*="background"] {
	color: #202122;
}

The first one prevents specific color/background attribs on the table cells from having any effect, but the second rule assumes the cells have a custom background and sets a dark text color.