Shopify Marketplace Connect includes a default template that is 100% compliant with eBay's 2017 Active Content changes.
If you have edited the template or created/imported your own template, then these may not be compliant.
It is your responsibility to ensure any non-default templates are compliant prior to the change that is reported to be in June 2017. To be compliant you can either change to our default template (you will need a 'clean' (non HTML) description to do that), or edit the template yourself or engage the services of a 3rd party designer.
For further assistance, please reach out to firstname.lastname@example.org