The dividing line in "Platform Browser" window is wider/brighter than in the "Build Profiles" window

Steps to reproduce:

1. Create a new project
2. Go to "File" ->"Build Profiles" 
3. Observe the line, which separates the "Platforms" list from the details window
4. Click the "Add Build Profile" button
5. Observe the same line in the "Platform Browser" window

Actual results: Lines are different. A screenshot is added below.

Expected results: Lines should be the same.

Reproducible with versions:  6000.1.0a10, 6000.1.0b1, 6000.1.0b3.

Not reproducible with versions: 6000.0.35f1, 6000.1.0a9.

Can’t test with versions: -

Tested on (OS): Apple M1 Max - Sequoia 15.1.1