Tinker Board S R2.527 GPIO button plugin broken

In the above mentioned configuration, I am unable to get any of the GPIO button plugin working.
During WebUI configuration, there seems to be a timeout as configuration takes exceptionally long. After configuring, the config seems to be forgotten, as the WebUI remains in its previous state.
For some reason /data/plugins/system_controller/gpio-buttons/config.json reflects the changes, but e.g. shutdown never happens.

Yes, I know what I am doing as I have this running on the RPi3.

This plugin needs a fix.

BR
Uwe