id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
22949	More Accurate and Extensible MIME Type Handling	mattonomics		"In the general case, a file extension may represent more than one MIME type. Currently, file extensions are married to a single MIME.

Specifically, let's look at the case of the ""ico"" file extension. Officially, the MIME type for this file should be ""image/vnd.microsoft.icon"". Unofficially, ""image/x-icon"" along with many others are usable.

The solution to this problem is extremely simple.

First, allow key => value pairs in the exhaustive MIME list located in wp_get_mime_types to be arrays so we can account for cases such as ico.

Second, add the proper handling for this change in wp_check_filetype. The way I have written it should not interfere with existing uses of this function (as they were all passing strings and now can pass a string or array)."	enhancement	new	normal	Awaiting Review	Media	3.5	normal		has-patch