Set iframe featury policy / allow attribute options

[ganesh-rao]

I'm developing a couple of templates that need features enabled by the allow attribute of the iframes.

Is there an option to set these anywhere? If not, any plans for enabling this please?

Across the visualisations I'm working on the following policies would range from critical to useful to have:
clipboard-write
geolocation
accelerometer
gyroscope
magnetometer
fullscreen