after no reaction in the German forum I hope this one is read by one or another developer or experienced user who can help me.
After dropping an attempt to install TikiWiki some years ago (V 14 back then) I have started a new installation with V 20 - and TikiWiki has improved a lot since!
I have only a handful of small issues and I'm almost sure that most of them can be solved easily. Two Issues are associated to the visibility of information - and saying this I think I am right with these in the "themes" forum.
I have chosen FIVEALIVE (as mentioned in the topic) in the Standard color setting, which looks quite good. The old site is also white/blue, so the colors are familiar to my community users. Okay, the form fields would look better in a light yellow instead of light pink, but that's really just my personal point of view. No problem to work with.
Wiki, Blogs, the Forum and thread overview - all looks fine. But if you open a thread you see... white text on white ground. If you mark with the mouse you see the text. If you don't you think, the text is missing.
A similar problem occurs in the own User Profile. You have My Tiki, Settings, About me, Watched Items (?) and a dropdown menu "More". If you open this menu the entries are blue text on blue ground...
Now the core question is: How to solve such issues?
I have found the form for "User defined CSS" in "Look & Feel", when the configuration is set to advanced... but that is like sitting in a 747 without a training or manual. And https://themes.tiki.org/Modifying%20a%20theme is... empty.
So I'm still lost...
Thanks for your help and