How to reproduce:
1. Open the attached project "case_1377544.zip"
2. Enter Scene "SampleScene" (Assets > Scene)
3. Open the Scene view
4. Enable the "2D Mode"
5. In Hierarchy window double click GameObject "Canvas"
6. In the Scene view click on a point in the red square that overlaps with all the squares under and observe the selected GameObject in the Hierarchy
7. Repeat 6th step 11 times

Expected result: The GameObject selection cycles from the top rendered element to the bottom rendered element
Actual result: The GameObject selection is determined by some other factor

Reproducible with: 2020.1.0a9, 2020.3.23f1, 2021.1.28f1, 2021.2.3f1, 2022.1.0a15, 2022.2.0a4, 2022.2.0a12
Not reproducible with: 2019.4.32f1 2020.1.0a8, 2022.2.0a3

Note:
- In 2021.2.0a19 and above the issue only reproduces for the first cycle of clicking through all the UI elements