Create a type and then click in it to open it in the editor.
In DB explorer make drop…it will not close the editor tab and if switch the tab it will give an error.
I think It should give you an message like when you drop a table with the table editor open.
In the code editor, we have some technical issues that we will need to do the status check of of the object when you focus on the object tab, and force closing the object tab when it does not exist any more due to some stability issues.