How to reproduce:
1. Open "SampleScene" Scene in the attached "case_1153027.zip" Unity project
2. In the Hierarchy tab, select the GameObject "Plane"
3. In the Inspector tab, select "Edit cloth self/inter-collision" inside the Cloth Component
4. Drag-select the "Plane" GameObject in the Scene tab
5. In the Cloth Self-Collision and Inter-Collision window, untick "Self-Collision and Inter-Collision"
6. Re-select the GameObject "Plane"
7. Repeat steps 3 and 4
-- Notice the "Self-Collision and Inter-Collision" checkbox

Expected result: the Self-Collision and Inter-Collision box remains unticked
Actual result: the Self-Collision and Inter-Collision stay applied to the Cloth Component

Reproducible with: 2017.4.26f1, 2018.4.0f1, 2019.1.2f1, 2019.2.0b1, 2019.3.0a2