Steps to reproduce:

1. Open a new Unity Project.

2. Open the 'Animator' window by navigating to Window > Animation > Animator.

3. Using the mouse cursor, attempt to resize the side section containing Layers/Parameters by holding down left click on the bar between the main and side section.

4. Move the mouse cursor left and right to attempt to resize the section.

Actual results: The side section resize does not align with the position of the mouse cursor.

Expected results: The side section resize aligns with the position of the mouse cursor.

Reproducible with versions: 

• 6000.0.10f1
• 2023.2.18f1

Not reproducible with versions: 

• 2023.2.17f1
• 2022.3.36f1
• 2021.3.40f1

Can’t test with versions: 

Tested on (OS): Windows 11

Notes:

• When side section is at it's smallest size, it can seem to the user that the resizing does not work at all, as the user needs to move the mouse cursor a distance away from the section before it will start resizing.
• When side section is not at it's smallest size, the section will initially snap backwards when the mouse cursor starts to move away from it.