While routing a four layer board, the tracks get very busy. There is this handy radio button that dims the layers you are not working on:
However, then i can hardly see them. Unfortunately my eyes are not what they used to be, so in the past this was probably not a problem. Is there a setting somewhere so you can turn this up just a little?
Thank you for any help.
Preferences->Common->High contrast mode dimming factor.
It is always a good idea to consult the preferences when looking for settings like this…
Fantastic, thank you for your help indeed!
It’s not that i did not search, but i must have overlooked it (It is under KiCad|Settings|Preferences|Common. The “Preferences” menu is about paths in my version)
And this setting was not mentioned in the online doc… (or is it 
)? An internet search did also not reveal it … but now it does!
Thanks again for taking the time to answer me. Best, Ruud.
You are right. I tried to find help, just for the fun of it: nothing.
So I withdraw my mild rebuke 
If there are missing elements of documentation, please file a GitLab issue for it. With such a complex piece of software we will have areas that can be improved 
In the case of multiple layers, this is just my personal opinion, but I feel that if the color changes every time the working layer changes, the continuity of the afterimage in my mind becomes weaker, so I work using settings like this.
Combine the color theme and the following settings to find the environment that is easiest for to use.
@johnbeard recently wrote these comments on visibility which are still available as this FAQ.
Maybe this could be of use?