Reproduction steps:
1. Open the attached user's project "InputSystem Bug.zip"
2. Connect a xinput compatible controller
3. In the Project Window under the "Scenes" Folder open "SampleScene.unity"
4. Enter Play Mode
5. Hold Button A (South Button) on the controller
6. Observe that the debug message in the Console Window "TestControl was pressed this frame" only appears once
7. While still in Play Mode bring the Editor out of focus
8. Hold Button A (South Button) on the controller
9. Observe that the debug message in the Console Window "TestControl was pressed this frame" is continuously printed

Expected result: debug message in the Console Window "TestControl was pressed this frame" only appears once when the Editor is out of focus
Actual result: debug message in the Console Window "TestControl was pressed this frame" is continuously printed when the Editor is out of focus (See attached InputSystem.mp4)

Reproduces on: Input System 1.0.0, Input System 1.1.0 - preview.2 (2019.4.26f1, 2020.3.7f1, 2021.1.6f1, 2021.2.0a16)
Could not test: Input System 1.1.0 - preview.3 due to the input not being registered when the Editor is out of focus

Devices used for testing:
Xbox Series X wireless controller