Steps to repro:
1. Open the attached project and 't1' scene;
2. In the Lighting window click on any input field (i.e. Direct Samples) and type some value (i.e. 1);
3. Observe that the typed value is shown in the Lighting window;
4. Click either on the Inspector or Hierarchy tab to switch them;
5. Click back on the Lighting tab to restore it back;
6. In the Lighting window click on any input field (i.e. Direct Samples) and type some value (i.e. 1).

Expected result:
The typed value appears in the Lighting window under the corresponding field.

Actual result:
The previous value in the highlighted field remains the same after typing some value after switching Editor tabs. See the attached video.
Regression introduced in version 2020.1.0a23.

Workaround is to restart Editor.

Notes:
- Reproducible in 2020.1.0a25, 2020.1.0a24, 2020.1.0a23;
- Not reproducible in 2020.1.0a22, 2019.3.3f1;
- Reproducible on Windows and OSX;
- Reproducible for both Lighting window and Lighting exposure window;
- Reproducible only when typing values in the Lighting window; not reproducible when typing values in the other Editor tabs;
- Reproducible only when typing values, not reproducible when dragging th presssed cursot in the Editor UI field corners.