How to reproduce:
1. Open any Unity project
2. Observe the Editor UI

Expected Result: All UI elements are clearly visible and distinguishable
Actual Result: Text and some graphical UI elements slightly blend with the background

Reproducible in: 6000.0.7f1, 6000.0.31f1, 6000.1.0a8
Not reproducible in: 2021.3.46f1, 2022.3.54f1, 6000.0.6f1

Reproducible on: Windows 10 (by User), Windows 11
Not reproducible on: No other environments tested

Notes:
- This issue was introduced in Unity 6000.0.7f1, where the Editor interface was slightly changed, introducing a new Editor palette. More details can be found in the release notes - [https://unity.com/releases/editor/whats-new/6000.0.7#notes|https://unity.com/releases/editor/whats-new/6000.0.7#notes])
- The Light theme is affected more severely by this bug