Godot version:
Master (cf124b1), upcoming Godot 3.1 alpha 4.

OS/device including version:
All desktop platforms with mouse input (Linux, *BSD, macOS, Windows, HTML5)

Issue description:
We just merged a handful of PRs which aim to improve and harmonize the mouse input on all desktop platforms. Some of those had been well tested and debugged during their developments, while others are still in need of more tests, but those were not happening with the PRs taking bitrot.

Hence this issue; we need you to test the current master branch (cf124b1, Calinou's next nightly build, or the upcoming Godot 3.1 alpha 4 on Sunday/Monday probably) and report any input regression that you may experience.

List of input PRs that were merged today:

• Use XInput2 RawMotion to generate MouseMotion events #19191: Use XInput2 RawMotion to generate MouseMotion events [Linux/*BSD]
• Unified button mask behavior across platforms #20063: Unified button mask behavior across platforms [Linux/*BSD, macOS, Windows, HTML5]
  • And Linux fixup: Fix middle and secondary mouse buttons order #24371: Fix middle and secondary mouse buttons order
• Fixes is_pressed when holding double click. #20081: Fixes is_pressed when holding double click [All platforms]
• Added double clicking to all buttons on Linux and Javascript #20385: Added double clicking to all buttons on Linux and Javascript [Linux/*BSD, HTML5]