Microsoft has updated Chromium to detect metered connections, and have implemented the feature to manage automatic updates in the browser.
When proposing the updates to Chromium, Microsoft notes that the browser currently detects metered connections by assuming cellular connections are metered connections, whereas more than 30% of cellular connections are marked as unlimited.
Microsoft proposed a better solution would be the built-in IsConnectionMetered API, which makes fewer assumptions.
The change has now been implemented in Edge Canary and the browser will now offer the option of now downloading browser updates over metered connections, with the following text:
Download Updates over metered connections
Automatically download updates over metered networks (for example, mobile network) and apply them on browser restart. Charges may apply.
It is likely a similar change will also show up in Chrome in the near future.