**System Information**
Operating system: High Sierra
Graphics card: ATI Radeon HD 4670 256 MB
**Blender Version** 2.8
Broken: (example: 2.80, edbf15d3c044, master, 2018-11-28, as found on the splash screen)
Worked: (newest version of Blender that worked as expected)
**Short description of error**
I can't get one brush stroke on GreasePencil2D without glitching large bars and pixels, I'm trying to learn Blender so I'm not really sure what is going on.
**Exact steps for others to reproduce the error**
Based on the default startup or an attached .blend file (as simple as possible).
Open 2D/3D Animator, draw one stroke, pixel glitches and no line formaton.