version: 2.80 (sub 39), branch: blender2.7, commit date: 2018-12-23 21:42, hash: e5e885d0ecb9, type: Release
build date: 23/12/2018, 17:14
Short description of error
When using a pen, as in a Microsoft Surface or similar device, using the camera Gizmos and moving the pen outside the 3D viewport seems to return null/invalid coordinates, and it breaks. They can ONLY be used inside the 3D viewport. It's an absolute deal breaker for touch screen users (Surface, Wacom, etc)
Exact steps for others to reproduce the error
Based on the default startup or an attached .blend file (as simple as possible).
Any default .blender. On a touch device using a stylus pen, click on a Gizmo (axis, zoom, or drag) and move the pen outside the 3D viewport.
When using a regular mouse the cursor gets hidden and it works as intended.