Multisite SVG uploads are served with incorrect mime/type

[jhawksley]

wp-includes/ms-files.php returns [text/xml] for SVG files, not [image/svg], which breaks their display.

[johnbillion]

Thanks for the report jhawksley, and sorry nobody has gotten back to you until now.

By default, WordPress does not allow SVG files to be uploaded for security reasons. Are you running a plugin which enables SVG files to be uploaded?

If so, it should be hooking into the upload_mimes filter and adding the text/xml mime type in there. Can you confirm whether this is the case please?

[jhawksley]

That is not the case. Even when setting mime type as image/svg, ms-files.php still sets the header as text/xml.

[SergeyBiryukov]

Replying to jhawksley:

That is not the case. Even when setting mime type as image/svg, ms-files.php still sets the header as text/xml.

I could not reproduce this with the code from comment:1:ticket:20990.

ms-files.php uses wp_check_filetype() and falls back to mime_content_type():
tags/3.8.2/src/wp-includes/ms-files.php#L32​.

If the correct image/svg+xml type is added via upload_mimes filter, then wp_check_filetype() returns that.

Otherwise, mime_content_type() is used, which depends on server configuration (see comment:10:ticket:25224).

This appears to be a duplicate of #24251 and #26256. See also #25224 and #26591.

[wonderboymusic]

This works - see image above:

function ___mime_types( $mimes ) {
	$mimes['svg'] = 'image/svg+xml';
	return $mimes;
}
add_filter( 'mime_types', '___mime_types' );