The menu text color on the green highlighted selection is unpredictable (white or black)…
I created a publicly deployed app which shows the menu like this:
I copied this app to create a similar app which is in prototype and it shows the menu like this:
I combed through my settings but couldn’t find the cause
Go to UX -~> Brand -> Style to see where these settings are
they are set to exactly the same thing, the first and third styles are inconsistent between the two apps in multiple ways: the text changes color (green (primary color) or white or black) and the formatting is different.
Its as if something is locked in and has to be re-locked using some secret sequence that I accidentally didn’t do the same way
Another test: I chose the third style and toggle light-dark theme. In one app the selected menu item text remains white, in the other app it turns black.
Also of note, I have #A0BB3C set as my custom primary color in both cases.
I’m experiencing a similar issue that started today.
Dark Theme + Primary color: #ecff00 (neon-yellow)
Before when using style “Accented footer”, menu text/icons were rendered dark.
Since today, text/icons display in white in the very same, yet existing App (in contrast to the situation of the OP).
Same is true for Action button icons with Prominence “Display overlay”.
One hardly can read/see the text/icon. 
Switching to style “colored”, menu text/icons correctly switch back to a dark grey (inactive tab) and black (active tab), but the icon on action buttons are still white.
Furthermore, I realise that calendars forth and back arrow icons (used to switch weeks) remain black when dark theme is chosen. One can hardly spot them.
Dark theme with accented Footer style
Dark theme with colored style
What can I do about it? 
This appears to be a part of the new “Material Design”:
It is not configurable.
I’m ok when it is not configurable whether a dark or clear font color should be used. But I find it quite inconsistent in “colored style” when menu text is black but action icon is white.
Black buttons to switch the weeks in calendar view also do not work out when using dark theme. A situation that definitely should be fixed in my opinion.
I agree! I’ve shared your post with the UX team.
great, thanks Steve!
and also that two of my apps configured identically behave differently.
Thanks for posting about this everyone. If anyone is still experiencing this issue, can you toggle to light mode, and then back to dark mode? I believe this should fix the issue. – it’s related to when your settings were saved. I’m also investigating an automatic fix, but this should at least address the problem in the short term.
