Hello @Jean Seb,

Welcome to the Klaviyo Community! 

That’s certainly an odd behavior that a signup form set to "Desktop & Mobile" is displaying when viewed on a desktop device but not on a mobile device. One reason I could think of that could be causing this is that for some reason, the Klaviyo.js - which allows for Klaviyo signup forms to be published onto your website - is either being blocked or omitted from loading on the mobile version of your site. I would advise reaching out and speaking with your site developer to investigate further to see if this was the cause for this behavior.

Along the same train of thoughts, if you were testing this on an actual mobile device and not through a chrome inspector tool, I would check to make sure you don’t have something like an ad-block app installed on your device. Ad-blockers and some anti-viral software/apps whose main goal is to prevent ads from being displayed would cause this behavior. If you have these apps installed, then it would be expected that you aren’t seeing a signup form appear when testing. 

I hope this helps!

David

Thanks a lot, your reply helps me in solving the pop-up issue in my Shopify mobile app development project. Keep supporting us in our coding journey.