Why isn't my checkout extension URL updating on Heroku?

[EricH2]

I've followed the steps in https://shopify.dev/docs/apps/deployment/web , and the app is fully working on heroku, apart from the checkout extension element. It's still being fetched at the autogenerated cloudflare-url/extensions instead of my heroku url. I've updated my .toml files to use the heroku urls. I've searched my codebase for the code that fetches the page for the checkout extension, but couldn't find it. Has anyone seen this before/has ideas about how to debug?

[SteveMonsen]

This happened to me with a post-purchase extension while using the Shopify post purchase browser extension. The dev/tunnel URL was being added by the plugin. I just opened the extension's Options, removed the URL, and saved. That fixed it.