I'm currently designing a website in SXA. I've encountered an issue wherein the contents of a Tab is appearing in Desktop, but not in Mobile. Inspecting the mobile markup, only the texts in the tab is missing, the tab structure itself is there. Also, if you'd notice the change from Tab to Accordion in mobile, we changed the code of the Tab a bit so that the component can change to an Accordion when in mobile.
This is a bug introduced in SXA 1.5
Please contact Sitecore support, they will provide you a hot-fix for this. The code change is required.
For now, without any code changes, you can mitigate this issue by copying presentation details from
Turns out that this is even better for you as you will be able to switch rendering without custom code