@template-extends

@template-extends is a recognized alias for @extends: the two spellings parse identically and produce the exact same ExtendsTag instance. The longer, template- prefixed spelling makes the connection to the class's own @template parameters explicit, which some codebases prefer.

Both snippets above parse to the same ExtendsTag, exposing the same $type property. See @extends for the canonical reference on this tag's grammar, exposed shape and origin.