In Shadow DOM spec there's selectstart event in the list of events that always must be stopped (https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#events-that-are-always-stopped). Selectstart event is supported by IE, Safari and Chrome but not part of HTML 5. Should this event really present in the list?
If it helps implementers to get the behavior right, I am okay with mentioning unspecified event names. Also, since we're going to stop those even if they are synthetically created, it makes sense to just mention them anyway.
BTW, http://wiki.whatwg.org/wiki/Specs_todo#APIs <-- selectstart was added as one of the TODOs.