**System Information**
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 1080 with Max-Q Design/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 466.47
**Blender Version**
Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-05-24 18:46, hash: `rB0606a37e1a8c`
**Short description of error**
Too often when weight painting it's impossible to paint over certain vertices.
**Exact steps for others to reproduce the error**
{F10147967}
Try to paint over the middle vertex (0 weight)
{F10147965}