Link account extension improvement

Hello,
I have forked https://github.com/sortlist/auth0-account-link-extension the auth0 account link extension https://auth0.com/docs/extensions/account-link-extension to allow to configure custom domains through rules config instead of by editing the source code of it https://github.com/auth0-extensions/auth0-account-link-extension/pull/78.

Everything is working fine except that I am not able anymore to access the config of this extension to edit the theme of it through the auth0 interface after a refresh of the page. On the page that lists all installed extensions (see all-extensions.har file), I don’t have the ‘setting’ icon for the extension and when I click on the name of the extension, I have a new tab that open on my browser that end with a 504 status.

how can I find where come from this bug?