my website doesn't work only wihth Firefox

works fine whith Chrome and Safari on iphone but not with with Firefox

With Firefox it appears like desktop device

url of my web site : www.letremplin-isere.org/
an idea why ?

thank you for your help

Which version of Mobile Joomla do you use, Community/Basic or Pro?
And what is User-Agent header of your Firefox for iPhone?

You can check User-Agent header at www.mobilejoomla.com/uatest.php

User-agent: Mozilla/5.0 (iPhone; CPU iPhone OS 12_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/13.2b11866 Mobile/16A366 Safari/605.1.15

I use Community/Basic version of Mobile Joomla

This User-Agent header is detected correctly by our remote device detection (part of MJ Pro). Current version of Community/Basic version doesn't detect it, but next version will do it. Most likely next version will be released in few days.