Steps to reproduce:
1. Open the attached “Repro“ project (link in the internal comments)
2. Open the Package Manager window
3. Install the Cloud Diagnostics package by searching for it in the “Unity Registry” and clicking the “Install” button
4. Click the “Configure” button (in the same place where the “Install” button was located before installation)

Expected results: The Project Settings window opens with the “Cloud Diagnostics” category displayed in the details pane
Actual results: The Project Settings window opens up with a blank details pane, and “Cloud Diagnostics” and “Environments” categories do not appear in the list after the package installation (the category list is still visible, but no category is selected because the requested one is missing from the category list)

Reproducible with: 2022.3.62f1, 6000.0.0b11, 6000.0.49f1, 6000.1.4f1, 6000.2.0b3
Cannot test with: 2021.3.52f1 (Cloud Diagnostics package unavailable), 2022.3.61f1, 2023.3.0b10 (project crashes on launch)

Reproduced on: Windows 11 Pro (24H2), Intel macOS 15.3.2
Not reproduced on: No other environment tested

Workaround:
- After installing or removing the Cloud Diagnostics package, restart the Editor

Notes:
- Not reproducible in a new project
- Removing the “Cloud Diagnostics” package fails to update the Project Settings window, leaving the “Cloud Diagnostics” and “Environments” categories still available for selection. However, when trying to open them, an “ArgumentNullException: Value cannot be null.” exception gets thrown in the Console (see full error message in the internal comments)
- The issue reproduces both with the oldest (1.0.3) Cloud Diagnostics package version and the newest (1.0.10) (the 2023.0.0a1 Editor version was used to test different package versions)
- Even if this issue happens By Design due to compiler errors in the project, there should be a warning or a prompt to restart the Editor in case of a failed package and/or Project Settings window compilation (similar to the Burst package), instead of silently failing