How to reproduce:
1. Open the attached “hexCode.zip” project
2. In the Project window, select “New Material.mat”
3. In the Inspector window, open the color picker window
4. In the Hexadecimal field, insert “FF0000 ”
5. Observe the result

Expected result: Hexadecimal field shows “FF0000”
Actual result: Hexadecimal field shows “FF0000 ”

Reproducible with: 2021.3.31f1, 2022.3.12f1, 2023.1.18f1, 2023.2.0b15, 2023.3.0a11

Reproduced on: macOS 13.5.2 (Intel)
Not reproducible on: No other environment tested

Note: if the Enter key after the 4th step, the Hexadecimal field gets reverted to the old value