Well, we can discuss and argue that for hours. I marked this topic as solved as this is a workaround which works. So, if someone comes here, he can downgrade to 5.7.7 and he will be able to edit his posts again. And there is now drawback as the changelog between 5.7.7 and 5.7.8 doesn’t show lots of changes. So, you can perfectly live with version 5.7.7 and wait a few days for the version 5.7.9 to arrive, with the bugfix.
