In the last episode of last season (5) of Star Wars: The Clone Wars, I encountered a new category of guards. They were placed in the Jedi Temple & were using lightsabers.
As far as I know, Jedi had a high-tier of identity who couldn't be placed under mask as security puppets (Even clone troopers used to speak freely, but these Jedi temple guards were fully silent even when Jedi were discussing something). So, it seems unlikely to me that they were Jedi.
But, as they were using lightsabers (although, it was never displayed how efficiently they could use them), so it seems unlikely to me that they weren't force sensitive.
They also don't look like robots using lightsabers.
Who were they, really? Have they ever appeared in canon before?