Not able to delete a tab

AnTul vor 9 Jahren aktualisiert von Alex Jenter vor 8 Jahren 3
The latest version. Do not give delete tabs. SQL error 19. 
Wird überprüft
Thanks for the report!
Most probably your database is corrupted. Please export it to XML, create a new notebook, and import the XML into it. After that deleting a tab will become possible.

About not remembering position: please report in a separate ticket. Thanks!