Manual:$wgMimeType

From Linux Web Expert

<translate> Output</translate>: $wgMimeType
The type to send in the Content-Type header.
<translate> Introduced in version:</translate>1.3.0
<translate> Removed in version:</translate><translate> still in use</translate>
<translate> Allowed values:</translate>(string)
<translate> Default value:</translate>'text/html'

Details

The type to send in the Content-Type header of pages. Set to 'application/xhtml+xml' if you want pages to be treated as XHTML. Also 'application/xhtml+xml' is necessary to display MathML properly in Mozilla.