Fix 1.21.9+ adapter loading for older versions

[SirYwell]

Overview

Description

The 1.21.9 adapter was loaded on older versions, e.g., on 1.21.8, failing with exceptions when trying to edit something.
Let's make sure it doesn't load on older versions.

Submitter Checklist

• Make sure you are opening from a topic branch (/feature/fix/docs/ branch (right side)) and not your main branch.
• Ensure that the pull request title represents the desired changelog entry.
• New public fields and methods are annotated with @since TODO.
• I read and followed the contribution guidelines.