Reproduction steps:
1. Open the user’s attached project
2. Open “Assets/TouchTestScene.unity”
3. Click File > Build Settings > Add Open Scenes
4. Click Build
5. Open “DesktopTouchTest.exe”
6. Make the window fullscreen and touch & move everywhere
7. Observe the “Mouse 0” input and notice it stays false
8. Make the window width 1/4 the size  (press alt+Enter to leave fullscreen) and touch everywhere
9. Observe the “Mouse 0” input becomes True when moving the finger

Expected result: “Mouse 0” input is False
Actual result: “Mouse 0” input is True

Reproducible with: 1.3.0, 1.4.1, 1.4.2 (2020.3.39f1, 2021.3.8f1, 2022.1.14f1), 1.4.2 (2022.2.0b6, 2023.1.0a9), 1.6.1 (2021.3.46, 2023.2a19)

Reproducible on: Windows 10 Pro 21H2

Notes:
1. Press Alt + Enter, to change build from fullscreen to windowed mode
2. Also reproducible with Legacy Input System