Reproduction steps:
1. Open the attached “ASDQWE” project
2. Build and run the WebGL Player (File > Build And Run)
3. Open Finder or File Explorer
4. Go to the Build location
5. Open index.html and uncomment line 78 (config.autoSyncPersistentDataPath = true;)
6. Refresh the browser window with the Player
7. Observe the Player

Expected result: There are no issues
Actual result: The Player throws a "TypeError: Cannot read properties of undefined (reading 'length')" error on start-up

Reproducible with: 2022.3.52f1, 6000.0.27f1, 6000.1.0a4
Not reproducible with: 2021.3.46f1

Reproducible environment: MacOS 14.6.1 Intel, 15.0 Intel (user’s)
Not reproducible environment: No other environment tested

Workaround: Set config.autoSyncPersistentDataPath to false or leave the line commented out

Note: The user reported seeing the issue occur persistently on Firefox and seldom on Chrome. CQA could not reproduce the problem on Firefox 132.0.2 only on Chrome 131.0.6778.69, Safari 17.6