How to reproduce
1. Create a new project and install the Probuilder package
2. Ensure the Editor is in light mode (Edit > Preferences > General > Editor Theme)
3. Observe the result on the Tools Toolbar

Expected result: Buttons appear the same as the others
Actual result: Buttons appear to be disabled

Reproducible with: 6.0.1-pre.2 (6000.0.0b14), 6.0.5 (6000.0.51f1, 6000.1.7f1, 6000.2.0b5)
Could not test with: 5.2.4 (2022.3.63f1), 6.0.1-pre.1 (2023.3.0a14) (no “Create Cube” or “Create Polyshape” button)

Reproduced on: Windows 11
Not reproduced on: No other environment tested

Note: The buttons still work, just appear disabled