I was too fast and hit delete to trash link instead of the update button. I have look into the database to got the original fieldnames. That is a nightmare.
No it is something stranger. And not the first time:
I have this got earlier that all the fields are removed from the Custom Field after that I moved them up and down. After hit save all is removed, only the Field Group page exist without any fields. I have some images of that.
Here you see. And it was not hitting the delete button, the the complete Fieldgroup was removed.
I can't reproduce this, but it wasn't the first time (see earlier post).
The only thing I did was moving the fields and hit save.
Sorry but I do not understand the issue totally. If you create new fields but do not save them for the first time, they will be removed from the field group if you click the "Move to Trash" button.
I add the first two fields and save them.
Another day I add two extra fields and save the again.
After that I move the fields (the last two to the beginning).
When I hit save the total Custom fields are empty.
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