Can't see the letter in tip block in IOS

[Dolores-Z]

I point it out in the picture (don’t know how to describe it in English…)

[bdrewery]

This only happens with a Dark "base theme".

[Fiv3286]

Setting base theme to light does solve it, but I myself don't like the look...
It's bothering me just enough that I might open a pull request if I can find the time :).

(I've modified the background colors for oled).