It was just FYI, there is no need to answer.

Thanks a lot for posting this update here, Ádám Biczó!

I see some apps in the App Store updated with "The Studio 2019 SR1 CU3 update introduced some breaking changes in the API. This update resolves it." comment in their release notes.

There used to be a practice to mention API changes in Studio release notes, e.g. in Studio 2015 SR2 CU6 or CU7, or Studio 2017 SR1 CU9.

However, I see absolutely no mention about API changes in the SR1 CU3 release notes... Why?

In the Language Developers group also nothing...

I think Evzen Polenka because they were not planned. We only discovered them during testing afterwards and with some feedback from users.  The change only affected a few apps and we don't test every single one of them unless we know there are changes.

Okay, so what now?
Will the breaking changes stay undocumented?

I'll discuss with the team tomorrow and we'll publish if appropriate.  It may be something that only affected the three apps we had that used Studio authentication... possibly not of interest to external developers.  It could also be that breaking changes was a poor description of the need for the update.

Yes, thanks Ádám Biczó, no doubt Daniel Brockmann was very happy to learn about this ;-)

Are there any news?

I see report about unexplained issues in using CU3 API: community.sdl.com/.../studio-2019-cu3-vs-cu2

None yet Evzen Polenka. But we will do this in due course after we finish investigating.  It's not a high priority for us at the moment but we have not forgotten and it is important to do as we are finding little discrepancies here and there that need explaining.