Hello,
I think it would have been helpful to announce that on the keycloak-user /-dev mailing-lists and Keycloak blog.
(In case it was announced - it was IMHO not stressed enough).
Some folks (including me) based their internal forks of Keycloak on top of a "maintenance branch" like 2.1.x
expecting to be able to channel compatible fixes / patches into the said custom fork.
With those maintenance branches now gone - this model no longer works.
Given that keycloak has now over 500 forks I guess that I'm not the only one who followed that model.
I would suggest to keep some maintenace branches for previous versions (e.g. 2.1.x) around to enable users
to upgrade their forks in a timely manner.
Cheers,
Thomas