Hi Andreas,
The version in the App store (1.5.1) seems not up to date with the content of the GitHub Repo. There is a fix included. https://github.com/mendix/DropdownDivConverter/commit/c5417e20308264edcbeaa244738eeeb51ab36b39
Please rebuild the widget from source to fix your problem.
I hope the someone from Mendix can release the fix in the app store all users
Cheers, Andries