How to permanently allow usage of camera on trusted websites with iOS - Safari

Unfortunately, it seems there is no way to permanently grant a website access to the iPhone camera within Safari (yet).

iOS 11 added the option to completely disable camera & microphone access in the Safari privacy & security settings. Having the camera & microphone access enabled for Safari, however, only means that Safari will ask the user for their permission when a website requests access to the user media.

Unfortunately, as of iOS 11.3, no further website-specific settings are available, so your users would have to confirm their permission every time camera access is needed on your website.

I'd like to reference the corresponding Apple Support page, but this question doesn't seem to be addressed there yet.

This is solved from iOS 13 onwards. With any website open, tap the "AA" icon in the top-left. Then tap "Website Settings" which will enable you to set camera permissions to "Allow" instead of "Ask".

Unfortunately this setting is not available before iOS 13.