Hi,
I have just set up an empty new project in Unity 2019.2.3 using the LWRP template and I have got an error when I imported the latest spine-unity 3.8 (updated 2019-08-29) and the Unity 2019.2: spine.lwrp-shaders 3.8 (updated 2019-08-13). The scene I was setting up is empty, as I said, with only Cinemachine and the (awesome) Corgi Engine 6.0.
I got the error and the warning you see in the attached image:

I have not yet imported the caracter from Spine to Unity.
Any idea on how to fix them?
Thanks

Harald wrote

We are sorry for the trouble! Actually this was a false alarm, you can click the clear button safely.

I have uploaded a bugfix that removes this wrong error message, you can download the new unitypackages from here as usual:
http://esotericsoftware.com/spine-unity-download

Thanks very much for reporting!

Thanks for the quick feedback. I'll try with the updated runtime as soon as I get back to the studio!