Theme headers not showing on dark theme

I have an issue with vertical grid card headers not displaying correctly when using themes.

If I choose a theme with a dark style, predominantly black with white headings and text, then the heading titles on nearly all cards show correctly. When I have used a vertical stack card, the title heading is dark, usually unreadable depending on which particular theme.

I have tried many different themes, this issue occurs on my android phone as well as my windows PC.

Am I doing something wrong, or is it an issue that I should be reporting as a bug?