The WebGL Diagnostics panel shows Total/Used JS Memory as N/A on Desktop browser

Steps to reproduce:

1. Open a new Unity project
2. Set Build target to WebGL
3. Go to Project Settings>Player>Publishing Settings and tick Show Diagnostics Overlay
4. Build & Run the project on a desktop browser
5. Click the diagnostics button next to the full screen button

Reproducible with: 2022.2.0a15, 2022.2.0b7, 2023.1.0a9

Note: this is not a regression because it's a feature new to 2022.2

Tested with Firefox 103.0.2 and Safari Version 15.5 (17613.2.7.1.8) on MacOS Monterey 12.4. The information is showing up correctly on Android Chrome 104.0.5112.97.