How to add a .xml extension to a specific URI using .htaccess
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I have a URL at the moment www.mydomain.com/feed/my_feed/ which writes out an xml document to be read by a third party. The XML document is dynamically generated (I'm using ExpressionEngine).

The third party have requested that it must have a .xml extension to be read.

Any ideas how I could set up a .htaccess rule to only use a .xml file extension for this particular uri?

Most tutorials are concerned with removing file extensions adding file extensions to all urls, which doesn't help a .htaccess noob.

Many thanks in advance.