id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
13500	Delay before seeing upload notifications after pasting image from MS Paint.	Steve James		"Win7/IE11/ckeditor instance in jQuery UI modal dialog.

I am seeing a noticeably long delay before seeing the progress notification when pasting a large image copied from MS Paint into an editor instance.
In Chrome, I see the notification right away.  In IE, a user may be inclined to think the editor is hung up when pasting a large file.
 

I think this could be a case of upload progress events not being consistently fired from one browser to another--you may need a smaller period to update progress.  I have seen this before.  It is important to show a 0% Progress Notification right away before initiating the upload (don't depend solely on progress events), so the user knows something is going on.
"	Bug	confirmed	Normal		Core : Pasting	4.5.0