If you forgotten something (e.g. a tracker) or re-edit a template to add/delete/move text, than move from "Templates" to "Marketing" to "Send Email ..." creates new EMPTY entry under marketing.
In Wizard moving from "Templates" to "Marketing" to "Send Email ..." should NOT create new EMPTY entry under marketing, but simply keep the original entry as this is an EDIT not CREATING.
In Wizard moving from "Templates" to "Marketing" to "Send Email ..." creates new EMPTY entry under marketing as the "Marketing Email Name" is empty when editing an EXISTING campaign.
The entry is visible in the campaing overview with EMPTY marketing name.
In Wizard moving from "Templates" to "Marketing" fill out the marketing name from the ORIGNAL (the campaign you are currently editing), this will stop creating a new marketing entry.
It does not really as the campaing still works as the new entry is appened and the email sending uses the first entry, BUT it adds an entry in the DB and its confusing in the overview and one does not know whether there is an error.
Hi @jobst
Thanks for reporting this.
If you get a chance to test the fix in the PR above please let me know if it works for you.
@PedroErnst because of #6173 I upgraded to 7.10.7 and therefor I am not 100% sure whether the suggested fix works.
The upgrade made a few changes to the Interface and also disabled a few things - for example it used to be possible in the Overview for any Campaign to delete entries below "Email Marketing" by hovering above the button on the right side, then select delete.
Now it only possible to edit, but then I cannot delete - so I cannot delete the entry and ALL of my campaigns have an "empty" entry below "Email Marketing".
Is there a way to delete entries in the Overview below "Email Marketing"?
This should still be possible @jobst, that part of the interface hasn't changed.

If you're not seeing something similar to this, then I'm not really sure what could be the cause. Which browser are you using?
@PedroErnst I went back today (sorry been really busy) and the "Remove" was there today. I tested it in Firefox and Chrome and it's there in both. I have no clue why it did not work for two days, but today it does.
@PedroErnst the fix works for me, thanks.