My BFS reviewer said the “shopify://admin/discounts” page doesn’t have a link to create my discount, which is not true.
As long as your app has a discount app function and these two fields, the link will automatically be created by Shopify, no matter what you do:
Another thing that I’ve noticed is that these stores have several apps installed that offer app discounts and none of them show up in his picture:
This is what he would be seeing, if there was no issues with his connection:
I’m going to resubmit the same app again, since he probably just got a 500 query from Shopify, but I’ll leave this comment here to any one who got unlucky and to protest against about some app reviewers standards.
Here is the entire rule for anyone curious:
5.5.4 Create high quality links: All links to your app from the Create discount
button on the discounts page must direct to a page in your embedded app
where merchants can create the corresponding discount. These pages must
follow all relevant App Design Guidelines. See this screenshot for your reference.

