CPU overwhelmed in split pane view (Scrivener 3)


Scrivener 3 slowed to a crawl for me. Looking at another thread made me check whether CPU usage was materially different in single pane view. It is, which I hadn’t considered as a cause because I’m in the split pane view 100% of the time and it wasn’t a problem with Scrivener 2.

Here’s what things look like when I’m typing in a split pane (99.4% CPU usage):

And this is what they look like in a single pane (6.9% CPU usage):

I’m running the latest version of the Mac OS (10.13.1) on a MacBook Pro (Retina, 15-inch, Late 2013)

I apologise if this has been discussed in another thread but I did search and couldn’t find anything exactly on point, just the threads that caused me to see what things looked like in singe vs split pane.