I am using 8.731 and still got the issue.
Using my level 112 night elf druid:
Tried deactivating most of my addons, then i reached dugiviewerz (and deactivated it) that i got back to normal fps.
Turning it on again, I was in the alliance legion herbalism guide, routing for dreamleaf. FPS went down to 1.5-ish.
Pick the option of no guide (clear guide?) and fps was back to normal.
Choosed the legion cooking guide, fps still at normal.
And again picked herbalism guide for legion, and a drop down to 1.5-ish.
Haven’t tried any other farming or routing points in the guides.