JS Navigator
Navigator exposes browser capabilities. Feature detection is more dependable than guessing support from a user-agent string.
Where to run this
Use a local browser project for this example. It needs browser permissions, additional files, a server endpoint, or a library as described below. The restricted playground cannot provide those dependencies.
A practical example
console.log("clipboard" in navigator);
console.log("geolocation" in navigator);
What happens
The booleans report whether those API entry points exist.