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Changes between Initial Version and Version 1 of Ticket #47987, comment 14

initial	v1
11	11	This is/should be handled by the UI as "uploading is in progress". The upload is not complete until all requests for post-processing are done. If the user reloads the page or navigates away while the upload is in progress, it will fail.
12	12
13		If the post-processing fails after all attempts, the final request is to do a "clenaup" (delete the new attachment). Then the UI should show an appropriate error message. In this case it should advise the ~~client~~ to scale down the image and upload it again, see https://core.trac.wordpress.org/browser/trunk/src/wp-includes/script-loader.php?rev=46289#L1237.
	13	If the post-processing fails after all attempts, the final request is to do a "clenaup" (delete the new attachment). Then the UI should show an appropriate error message. In this case it should advise the user to scale down the image and upload it again, see https://core.trac.wordpress.org/browser/trunk/src/wp-includes/script-loader.php?rev=46289#L1237.