Operating system: Darwin-18.6.0-x86_64-i386-64bit 64 Bits
Graphics card: AMD Radeon Pro 560 OpenGL Engine ATI Technologies Inc. 4.1 ATI-2.9.26
Broken: version: 2.80 (sub 74), branch: blender2.7, commit date: 2019-06-11 21:45, hash: rBd93a7290e506
Short description of error
I have an object that is emissive, and is set to Alpha Blend, because it has a gradient that fades to transparent.
It won't show the results, neither in viewport and rendered, only if I add an unconnected Diffuse or Principled BSDF.
Sometime it works even when disconnected multiple times from the material output.
But on a fresh start it won't work when set to Alpha Blend, and an unconnected diffuse or principled bsdf needs to be added in order to update the object with the material.