To reproduce:
1. Open attached project "1094277.zip"
2. Open Test Runner window
3. Select "NewTestScriptWithEnumeratorPasses" so it shows some information in the window console
3. Disable "Show tests that succeeded" in the top right corner (should be a green checkmark)
4. Try dragging the bottom console to the top

Expected result: you can only drag it until a button
Actual result: you can overlap the console on the buttons

Reproduced on:
2017.4.0f1 2017.4.14f1 2018.2.14f1 2018.3.0b8 2019.1.0a6