I would say is partially supported as depends on the platform, not really on the email coded as is exemplified here:
However, if other apps installed on a user's device can handle the same intent, users might not go directly to your app. For example, clicking a URL in an email from a bank might lead to a dialog asking the user whether to use the browser or the bank's own app to open the link.
So that depends on the configuration of the itents of the app to catch that request and how the user has configured the default handler on the device's system settings.