I don’t have a hub, it is directly connected to Homey (and still working).
How did you managed to get this connected? I don’t see this product in the list.
Install the test/experimental version of the app! IKEA Trådfri | Homey
Shortcut button working fine here since last (experimental) Tradfri version 1.14.2.
Could not get my Shortcut button to work. Connected it back to the Trådfri hub and it upgraded the firmware from 2.3.015 to 2.3.080, and after moving it back to Homey it now works. The upgrade process took 5 hours and drained the battery in the button.
Note that the battery did not get drained. It now appears that there must be a bug that gives low battery. With the previous firmware and the IKEA app, the only thing that worked was the battery indicator. Now the button works, but the battery indicator does not.