Feature Links accessibility validation

[Malvoz]

Ensure feature links work and make sense to keyboard and screen reader users:
https://maps4html.org/experiments/linking/features/

It might be a good idea to produce some questions for a tester, similar to #335?

[Malvoz]

Now that features links are focused on activation (#580), their featurecaptions are announced together with the link role which may be confusing to users since they've just activated that link. Question is if #580 was the right thing to do, and if so, should it be conveyed to users that they've pressed the link already? aria-pressed is only valid on buttons. Perhaps aria-current (whether set to "true" or "location") is appropriate, or even aria-disabled?

But maybe focusing the features (the feature links) themselves is not the correct thing to do after all, considering that with #636 it may make more sense than before to focus the map container?