Great job, Sherlock! You found the discount code for Google Shopping Feed Pro for Shopify by Apps Robots. Use the following code to get 10% discount:
doublefive
How to apply the promotion code?
Scroll down and look at the right for Apply a discount code.
Enter doublefive and press ok.
A popup comes with a Double High Five to you!.
On top you can Approve subscription with a discounted price.