A submenu disappears on MacOS when the MenuItem method argument "isVariableFunction" is set to "false" and priority argument is set to "-1"

How to reproduce:
1. Open the “DS Test 2023.zip“project
2. Navigate to Tools > Pixel Crushers > Dialogue System
3. Observe the submenus

Expected results: The “Tools“ submenu is visible
Actual results: The “Tools“ submenu is missing

Reproducible in: 2022.2.21f1, 2022.3.22f1, 2023.2.15f1, 6000.0.0b12
Not reproducible in: 2021.3.36f1, 2022.2.20f1

Reproduced on: MacOS 13.6.4 (M1,2020)
Not reproduced on: Windows 11 Pro (23h2)

Notes:

• When the “isValidateFunction“ argument is set to “false“ and then if the priority argument is deleted, the changes are saved, and the argument is added back, then saved again, the Tools main Menu in the Editor does not expand until the Editor is restarted (which could also be the initial issue that was reported)
• With other argument configurations for the MenuItem method, the “Tools” submenu is showing