And a thorough description of the problem / question:
I’ve recently noticed that sonarlint is incorrectly reporting the element as deprecated.
Both HTML5 Differences from HTML4 and HTML Standard have nothing saying that the element is deprecated, and the spec exists here: HTML Standard
It looks like it doesn’t have that ID format - vs code is showing: sonarlint(Web:UnsupportedTagsInHtml5Check)
I’ve also found the rule online here: HTML static code analysis
Thank you for reporting this. Digging deeper into the <hgroup> state, it did seem that in 2013 it was considered to be removed from the specification - here is a link that talks about its deprecation.
However, seeing that it is present in the w3 spec and mdn, I think we can remove it from this rule.