WebPush documentation assumes the reader know what a subject is

[Legioth]

trafficstars

https://vaadin.com/docs/latest/configuration/setting-up-webpush doesn't give any description about what "subject" refers to in this context but just assumes that the developer knows what it is.

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[tarekoraby]

There is this brief description: https://vaadin.com/docs/latest/configuration/setting-up-webpush#understanding-web-push. Do you think it should be expanded?

[Legioth]

All I see about subject is this line

The subject should be given as a url or mailto: since Apple web push server requires this.

How am I supposed to know what value to use in my case based on that description? Does it mean that the value should be one of those literals, or that those phrases somehow describe the expected format of the value?