Win10 Asus GTG1060
Broken: 2.78.5 hash 66383ea
Short description of error
when the rigify type panel from the bone properties panel is open, it makes that whole properties panel very slow, if you close it, it stops lagging instantly.
Exact steps for others to reproduce the error
go to addons and activate rigify addon.
create an armature
select a bone in pose mode
go to the bone properties panel
open the "rigify type" panel at the bottom
see how that whole panel is very laggy.