Repro steps:
1. Create a new shader graph
2. Make the graph inspector visible
3. Change the bounds of the Shadergraph window (either docked or undocked)
4. Try to resize the right or bottom sides of the internal inspector

Expected result: the right or bottom of the internal inspector resizes as expected
Actual result: resizing the right of the internal inspector moves the left side, and resizing the bottom moves the top

Reproducible with: 11.0.0 (2021.1.0b7, 2021.2.0a3)
Not reproducible with: 8.3.1 (2020.1.0f1), 10.5.0 (2020.3.8f1), 11.0.0 (2021.1.0b8, 2021.1.7f1), 12.0.0 (2021.2.0a4, 2021.2.0a17)
Could not test with: 2018.4.35f1, 2019.4.26f1, 2020.1.0b1 (graph inspector unavailable)