Sometimes strange behavior may be caused by a plugin or theme conflict. The fastest way to rule out conflicts is to deactivate all non-Yoast plugins and switch to a standard theme like Twenty Seventeen. If this resolves the issue, you have a conflict and should activate one plugin at a time until you locate the conflict. Finally, after all plugins are active, switch to your theme. This will narrow down the conflict to a specific plugin or theme.
If you are unfamiliar with checking for conflicts, we wrote a small guide that will walk you through the steps. You can find it here: How To Check For Plugin Conflicts
I have the exact same problem. Maybe a place to start looking: my Dutch site (apoplife.nl) does not have this problem. It just occurs on my English site (en.apoplife.nl). It’s not a conflict issue…
UPDATE: After I added a new post on my Dutch site the problem also started on the Dutch site, sorry to say. Shall I rollback to the previous version aslo, as that seems to work?
@barates If you have a similar issue, please open a new request. That way it’s easier to track issues and provide assistance. Thanks!