There is no limit on how many Properties windows can be opened

Unity: Inspector Framework

6.4.X

6000.4.0a1 onwards

6.3.X

6000.3.0b3 onwards

6.2.X

6000.2.6f1 onwards

6.0.X

6000.0.59f1 onwards

It is up to the user to decide to click multiple times. there is no limit elsewhere on how many property editor can be opened.

Steps to reproduce:

Create a new Unity project using the Universal 3D template
Enable Cameras overlay in the Scene View
Quickly click the "Open camera component properties" button in the Cameras overlay
Observe the Editor

Actual results: The user can open infinite amount of Properties windows

Expected results: There is a check if there is a Properties window for the GameObject already opened, it wouldn't open a new one

Reproducible with versions: 6000.0.58f1, 6000.2.6f1, 6000.3.0b3, 6000.4.0a1

Not reproducible with versions: 6000.2.5f1

Tested on (OS): Ubuntu 24.04, macOS Silicon Sequoia 15.6.1