How to reproduce:
1. Open the attached project “BounceRepro“
2. Open the “MainScene“ Scene
3. Enter Play Mode

Expected result: “TestCharacterActive” and “TEST2” GameObjects aren’t flailing
Actual result: “TestCharacterActive” and “TEST2” GameObjects are flailing

Reproducible with: 2021.3.27f1, 2022.3.1f1, 2023.1.0b21, 2023.2.0a18

Reproduced on: macOS 13.4 (Intel), Windows 10 (by reporter)

Notes:
- Changing the “Low Angular X Limit” “Bounciness” and “High Angular X Limit” “Bounciness” to 0 in the “Configurable Joint” Components of the “TEST_SPINE_0”, “TEST_SPINE_1” and “TEST_SPINE_2” GameObjects will stop the flailing, but setting this value lower e. g. 0.001 will cause the flailing to amplify
- Deleting the “TEST_SPINE_2” GameObject stops the flailing of the “TEST2” GameObject