How to reproduce:
1. Open the attached “IN-127952” project
2. Open the “SampleScene”
3. Enter Play mode
4. Select “GameObject”, in the Hierarchy
5. Focus on the Animator tab
6. Observe the Animator window

Actual result: Transitions are executed between sub-state machine and state/sub-state
Expected result: No transitions between states, while “Mute” it toggled on

Reproducible on: 2023.1.0a3, 6000.0.65f1, 6000.3.3f1, 6000.4.0b3, 6000.5.0a4

Reproducible with: macOS 26.2 (M1 Pro)
Not reproducible with: No other environments tested

Note: Transitions between states work as expected, only outgoing transitions from sub-state machines are affected