Hey Detlev,
Welcome to our Support Forum and thanks for writing in.
There are third-party factors that could affect our builder’s interface including the Design Cloud. One of those factors is browser extensions like an ad blocker. Some of our users reported that like in this thread and this. Please temporarily deactivate all browser extensions if applicable.
There’s also another case where the web host is messing up the character encoding of the website like in this thread. Please check out the thread and see if it’s applicable to you.
If none of those threads are applicable, please give us the following info in a Secure Note.
- WordPress Login URL
- Admin level username and password
- FTP access
Thanks.