Broken: version: 2.90.0, branch: master, commit date: 2020-08-31 11:26, hash: rB0330d1af29c0
Worked: new feature, wasn't on 2.83
Short description of error
In grease pencil: drawing on a converted mesh/plane creates new strokes to camera origin.
Also, if you delete everything on the converted mesh/plane Gp object and try to draw, new stroke is found on camera origin.
Not sure if this happens on other mesh conversions. Plane is the one it happens for sure. Found this by accident.
Please see the video.
Exact steps for others to reproduce the error
Start with 2D animation preset
Go to object mode
Create a mesh / plane
Rotate it 90 degrees X axis
Convert mesh to grease pencil
Change to camera view
Go to draw mode
Change material to stroke
Try to draw on the converted plane
Stroke is now found on camera origin as a dot.
This happens when you are viewing from the camera and when stroke placement is set to Origin / 3D cursor.
Also happens in front orthographic view > sometimes the stroke disappears or is found at the camera origin.
Also happens if you delete all the points of the converted GP object and try to draw from scratch.
If you have surface / stroke it seems to be ok.