pageblock head_top & pageblock head_meta , do not work in particles (at least in WP)

[joomlabeat]

I think this is still problematic:

#2303 (comment)

pageblock head_top & pageblock head_meta , do not work in particles - they only work in atoms.
Only pageblock head_bottom works

From a quick debugging I tried to do - they seem to be sent the html to the Gantry Document Html -addHtml() method.
But when the getHtml method runs, the html returned is empty.