Updating custom domain does not update magic link url correctly

Preflight checklist

• I could not find a solution in the existing issues, docs, nor discussions.
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• This issue affects my Ory Network project.
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Describe the bug

When updating the custom domain (to another domain), the /selfservice/methods/link/config/base_url value is not properly being set.

Reproducing the bug

1. Create a project
2. Set a custom domain
3. Use magic links
4. Send verification email (via oryapis.com, not via custom domains)
5. Set new custom domain
6. Send verification email (via oryapis.com, not via custom domains)
7. Verification link uses old CNAME

Relevant log output

No response

Relevant configuration

No response

Version

master

On which operating system are you observing this issue?

Ory Network

In which environment are you deploying?

Ory Network

Additional Context

There is a workaround - run the following command to reset this config value, which sets it to the correct custom domain:

ory patch identity-config <your-project-id> \
  --remove '/selfservice/methods/link/config/base_url'

Reproduce the sequence of changing a custom domain and sending verification emails, then inspect how /selfservice/methods/link/config/base_url is updated. Use the documented ory patch identity-config <your-project-id> --remove '/selfservice/methods/link/config/base_url' workaround as a comparison; done means new verification links use the latest custom domain without manual removal.