They make a spring loaded kit that includes a magnetic catch to help hold it closed - I think you can find more online - this is one example. They sell them as hands-free openers. You push it closed with your foot, and release the mechanism with your toe and the bunjee pulls it open. It stays open until you push it closed. We have dogs and this keeps them out of the trash. I _Really_ like the no-touch aspect - especially with kids in the house - the handle for the trash can was always gross. This way you don't touch anything with dirty hands.

You can remove the handle completely so there isn't anything for doggo to grab onto.

https://www.amazon.com/Door-Opener-Pull-out-silver/dp/B00AAZJ46G