Editorial: remove note about hidden being 'historical'

[marcoscaceres]

closes #63

[yoavweiss]

What's the best practice to indicate that some features are ones that developers should not be using, even if we don't have a clear path to deprecate and remove them?

[marcoscaceres]

I'd suggest us updating MDN for maximum reach - as most developers will end up there, rather than here... however, we can also mark things up as "best-practice"... but to be honest, specs making "best practice" suggestions is not great. I understand why we might want to encourage developers to use the enums, but still, using hidden doesn't seem to have any disadvantages over using the enum value.

[yoavweiss]

@igrigorik - thoughts?

[igrigorik]

What's the downside of providing guidance both here and in MDN? At the end of the day, the spec is the source of truth, not MDN. /cc @philipwalton for opinions™.

[marcoscaceres]

I guess I'm also questioning the validity of the advice: there doesn't seem to be any valid technical or performance or other reason to avoid using .hidden (that I can see - but please educate me if there is).

Given that .hidden seems to be non-harmful, and has no side-effects, we should really just leave it to authors to choose which is best for their code.

[npm1]

FWIW given that we do not intend to extend the set of possible visibility states in the near future I agree with this.