Upgrading from 7.8.4 to latest version

Hi

I'm using Bonita Studio community version 7.8.4 and I want to upgrade it to 2021.1 version.

Actually because of active users on version 7, I installed new version and move every process from old version to new version one by one, but in the first movement I saw some my custom widget doesn't work correctly!

What is best way for upgrade from version 7 to 2021?

Is it better using migration way?