Restrict version does not work

When restricting a specific version to a certain person all other people with editing rights can still edit pages of the specific version.

We created two versions: 0.1 and 1.0.
After that we set the restriction of version 0.1 to edit for one specific person (User-field set to “Julia…”).
After that I tried to navigated to a certain page (page was unversioned at that time) and choose the scroll version 0.1.
The Edit button was still visible and I clicked it.
I then could edit the page and publish the changes. The changes were visible to anyone and only in version 0.1

Expected behavior: The Edit button should not be enabled and I should not be able to edit a page of version 0.1.

Does anyone have an idea what the issue is? Is there something else to configure?

Thank you!

Best regards,

Gerald