Import/Export between different environments breaks dropdowns

[MatthiasG]

Hi,

I am trying to move an existing canvas app from one environment to another (create as new). After the import has finished everything looks fine. When I open the published version everything works fine as well, but when I open the app in edit mode all existing drop downs are broken and won't open after clicking on them in preview mode. I also tried to republish the app and see if it only affects the preview mode, but it's even worse. After clicking on a dropdown in the published app it crashes and restarts. In my investigations I also used the monitoring tool but it shows nothing about the clicked dropdown. No error, no warning just nothing. 

After trying different things I found out that the problem only occurs if I import the app in a different environment than the original app was exported from.

The drop downs are just basic drop downs with some styling, string arrays as items and have a local variable defined for the reset property. The whole app is using the responsive features of PowerApps for sizing and positioning of all controls.

I just don't know what I could try except of recreating all drop downs which is no solution for the problem. Thanks in advance.

Edit: This is the error, that gets displayed in the browsers console: