New general page: FTC tab gives React warning

[igorschoester]

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• I've searched for any related issues and avoided creating a duplicate issue.

Please give us a description of what happened

To Reproduce

Step-by-step reproduction instructions

1. Enable debug output (SCRIPT_DEBUG)
2. Visit Yoast > General
3. Notice the warning in the browser console:

Warning: Failed prop type: The prop onDiscard is marked as required in UnsavedChangesModal, but its value is undefined.

The useBlocker can return undefined for proceed (and reset) for specific states.
See their type def in the documentation: https://reactrouter.com/en/main/hooks/use-blocker

Expected results

1. No prop warnings

Actual results

1. Prop warning

Screenshots, screen recording, code snippet

If possible, please provide a screenshot, a screen recording or a code snippet which demonstrates the bug.

Technical info

• If relevant, which editor is affected (or editors):

• Block Editor
• Gutenberg Editor
• Elementor Editor
• Classic Editor
• Other:

• Which browser is affected (or browsers):

• Chrome
• Firefox
• Safari
• Other:

Used versions

• Device you are using:
• Operating system:
• PHP version:
• WordPress version:
• WordPress Theme:
• Yoast SEO version:
• Gutenberg plugin version:
• Elementor plugin version:
• Classic Editor plugin version:
• Relevant plugins in case of a bug: