How to serve legacy for chrome ios only on version 14.2 or less

We’re developing a WebRTC application and as you may know WebRTC on ios is only supported in safari but this has changed with ios 14.3

So I want to detect chrome for example and see if ios 14.3 or more is installed to serve the main module otherwise serve the legacy module which shows the user a message to upgrade their OS.

We’re using meteor/modern-browsers package and setMinimumBrowserVersions, previously we had chromeMobileIOS set to Infinity but now we want to set the ios version to 14.3, not chrome version, how do we do this?

There is an example here
https://blog.meteor.com/meteor-1-7-and-the-evergreen-dream-a8c1270b0901