I created a .odt with formulas on Windows 11 , white background & black text .
Then I migrated to Debian testing KDE , the inverse : black background & white text .
The .odt , I’m able to change only the color of the normal text to white by Select All , Font Color Automatic , the formulas remain black , how to white ?
Version : 24.2.5.2
Unfortunately you can’t. Formulas are “external” objects prepared by Math. These objects are not controlled by styles and therefore their look can’t be changed centrally. (Math has not evolved for years and lags far behind the other components regarding formatting configuration.)
What surprises me is the fact you need to force font colour to Automatic. This is the default configuration unless you already applied a different setting. It also shows you don’t use styles which are intended to separate appearance from contents.
PS: when asking here, always mention LO version because the application is alive and there are differences between releases which can impact the accuracy of answers.
On Debian testing KDE I chose Appearance , Breeze Dark so LibreOffice is black background & white text ( the inverse of Windows 11 ) .
I found Dark theme messing with formulas text color, white on white when print/export - #8 by JohnSmith_47 , " Anyway, to update the OLE objects to recognise the colour scheme click Tools > Update > Update All " , it works for me !