Operating system: Darwin-18.2.0-x86_64-i386-64bit 64 Bits
Graphics card: AMD Radeon Pro 560 OpenGL Engine ATI Technologies Inc. 4.1 ATI-2.4.10
Broken: version: 2.80 (sub 48), branch: blender2.7, commit date: 2019-03-14 22:54, hash: rB35b78d9807c4
Short description of error
I'm pretty sure that the Dynamic Paint's weight paint mode is not working, unless the UX has changed in some major way and I'm not understanding the new way it is supposed to work. I can confirm that the other modes (waves, texture paint) are working, albeit the texture paint mode has also proven to be somewhat finicky for the last few months, requiring some setting and resetting to get it stable.
Exact steps for others to reproduce the error
It should be all set up in the attached file, there is a monkey [canvas] and a cube [bush], the vertex group dp_weight has been created and nothing seems to happen, regardless of what mode I'm in - weight is not getting affected in any way that I can tell.