Reproduction steps:

1. Create a new project
2. Navigate to File → Build Settings…
3. Select WebGL Platform
4. Enable “Development Build” option
5. Build the Player (not Build&Run)
6. Navigate to the project folder using Finder for macOS/File Explorer for Windows
7. Open the build folder in Terminal for macOS/cmd for Windows by right clicking on the build folder and selecting the option “New Terminal at Folder“ for MacOS or “Open in Terminal“ for Windows
8. For mac in the Terminal execute command “ipconfig getifaddr en0“ to get your IP. For Windows, in the CMD execute command “ipconfig“, search for IPV4 field to find your local IP Address.
9. In the Terminal/cmd execute following command: “python3 -m http.server portnumber“, “portnumber“ can be any 4-5 long numeric value. For example 60281 (ensure that Python is installed)
10. Open the Player in the browser by typing “yourIP:60281” in the Address bar
11. Open the Profiler in Editor by navigating Window → Analysis → Profiler
12. Click on the “Play Mode“ dropdown, select option <Enter IP>
13. Enter “yourIP:60281” in the field, click “Connect“
14. Observe the result

Expected result: The Profiler receives data from the WebGL Player and outputs the result
Actual result: No data is received

Reproducible in: 2021.3.46f1, 2022.3.53f1, 6000.0.29f1 6000.1.0a6

Reproducible on: macOS 14.6.1 (M1 Pro), Windows 11
Not reproducible on: No other environments tested

Note:

* Tested with: Google Chrome (Version 131.0.6778.70), Firefox (Version 132.0.2)
* Cannot reproduce when building and running the player using “Build&Run“ without “Autoconnect Profiler” option enabled, it is not possible to connect to the Player that way.
* The Profiler manages to receive data only when “Autoconnect Profiler” option is enabled. This way, the data can be received if building the Player and running it manually or Building & Running