Terrible developer "support". No response by email for over two weeks so pasting contents here:
Ubar does not work as expected or described. There are multiple problems with multimonitor support – apps from one window appear in the other, etc. I currently have Slack, Miro, Around all open my second monitor, and they only appear in ubar on the first monitor.
It does not work with Microsoft teams – clicking the app name in ubar does nothing. Maybe more to do with teams and its floating notification window than anything specifically wrong with ubar, but other apps do not have this issue.
The finder tab is always in ubar, despite not having any windows open.
The space ubar takes up at the bottom of the screen is not “reserved” in the same way as other apps (eg context’s app drawer). This means the bottom 20px of all windows when maximised becomes invisible because ubar is sitting on top, unless the app is manually resized down.
In short: avoid.