Hi Yasar,
Refer this documentation : https://docs.mendix.com/refguide/moving-from-8-to-9
Hi Yasar,
Even I am facing the same Issue on client-based widget issues in the application
I suggest you to have look on this docx :https://docs.mendix.com/refguide/moving-from-8-to-9#studio-upgrade
before migrating it.
Cheers,
Narendran J