**System Information**
Operating system: Ubuntu 20.04 LTS (Linux-5.4.0-40-generic-x86_64-with-debian-bullseye-sid 64 Bits)
Graphics card: AMD Radeon RX 5700 XT (NAVI10, DRM 3.37.0, 5.4.0-40-generic, LLVM 10.0.0) X.Org 4.6 (Core Profile) Mesa 20.0.8
Graphics driver: amdgpu-pro-20.20-1089974-ubuntu-20.04
**Blender Version**
Broken: version: 2.90.0 Alpha, branch: master, commit date: 2020-07-10 20:07, hash: `rBd2b910fafec6`
Worked: none
**Short description of error**
After D7910, sampling on other windows should have worked but it still doesn't on Linux.
**Exact steps for others to reproduce the error**
Make sure to have 2 separate windows or instances of the same blender file.
Use eyedropper from one window to sample something on the next.
Eyedropper tool becomes a normal cursor once it leaves the window that initiated the tool.