We've introduced a
host query parameter as part of the URI that Shopify redirects to after the OAuth grant flow. This parameter represents the domain that hosts your embedded app and is needed to initalize App Bridge 2.0 in the Shopify admin.
For most apps, there is no action required following this change. This change might be a breaking change if your app's
hmac verification step doesn't verify the
hmac using all the parameters available in the redirect URI.
For steps to verify the
hmac parameter, see the "Verification" step of the Authenticate with OAuth guide.
To see what other changes are needed to use App Bridge 2.0, see Migrate your app to App Bridge 2