From Nils Breunese in SUPPORT-6740
Removing a dialog hotfix breaks the dialog

I can reproduce this on demo.magnolia-cms.com:
Go to the Resource Files app: Web Dev > Resource Files
Navigate to /tours/dialogs/components/tourCarousel.yaml
Click 'Edit file' to create a hotfix
Don't make any changes and select 'Save changes'
Click 'Delete file' to remove the hotfix and revert to the original resource
Now open the travel homepage and select the carousel at the top of the page and click its edit button.
A red bar appears saying: "An error occurred while executing an action."
After clicking [MORE] the following message text is shown: "Action execution failed for action: editComponent"
I expect the dialog to work as it did before creating the hotfix.