How can I fix duplicate canonical tags and product.url errors on Dawn theme?

I’m getting an error on Google console saying that 600+ of my products have ‘Alternate page with proper canonical tag’ and 700+ have Duplicate without user-selected canonical. To solve the issue I need to change {{ product.url | within: collection }}, but I cant find this code under snippet on Dawn theme - can anyone offer any help?

Following, looking for the solution too.
If you found any, please help.