System Information
Operating system: Darwin-19.6.0-x86_64-i386-64bit 64 Bits
Graphics card: AMD Radeon Pro 575X OpenGL Engine ATI Technologies Inc. 4.1 ATI-3.10.15
Blender Version
Broken: version: 2.90.0, branch: master, commit date: 2020-08-31 11:26, hash: rB0330d1af29c0
Worked: 2.83
Short description of error
Duplicating and mirroring mesh using cursor causes UV elements to appear outside of UV area.
Exact steps for others to reproduce the error
Set 3D cursor point, duplicate mesh element, mirror using 3D cursor pivot point (either x, y or z axis).
This occurs on factory settings with no addons.