Since an installation under Linux is working again (see installation-headaches-and-partly-fixes-on-ubuntu-20-04) I am happy to report, that with frontend winType="glfw" and screen=0 (or 1) I indeed can now chose between monitors, no matter which screen from the coder was called. And their refresh rates are as intended, according to output from timeByFrames. Verified on just one single test setup so far.