Reproduction steps:
1. Create a new project
2. Open Package Manager (Window > Package Management > Package Manager)
3. Press “+” button and select “Create package”
4. Enter any name and press enter to create a package
5. Select newly created package, Manage > Edit Manifest
6. In Inspector change Release field into invalid Unity version (e.g. Release: “9999999999999999b9”)
7. Apply changes and observe the Console

Actual result: “Failed to resolve packages: Invalid patch version. No packages loaded.” error is thrown and no changes to any of the packages can be done
Expected result: Apply button is disabled and “Invalid Unity Version” error is displayed or more informative error is displayed which shows package name and the field that needs to be fixed

Reproducible with: 6000.3.0b6, 6000.4.0a2
Couldn’t reproduce with: 2021.3.58f1, 2022.3.68f1, 6000.0.60f1, 6000.2.8f1 (No “Create package” option)

Reproduced on: macOS Sequoia 15.4 (M4), Ubuntu 22.04