I was trying to use this extension on my wiki (MW1.35) in a template to display different Main Page according to the device, but it seems not working.
I created Template:MP :
<nomobile>{{{1}}}<nomobile> <mobileonly>{{{2}}}</mobileonly>
When i use {{Template:MP|Main page for Desktop|Main page for Mobile}} it renders variables as plain text, and does not replace the content.