QtWebEngineProcess 100% CPU

QtWebEngineProcess is jumping to ~100% of CPU when I run RStudio Preview of a dataframe (960 rows, 20 columns)..

I am running:
MacOS 10.15
RStudio 1.2.5001
R 3.6.0 GUI 1.7 El Capitan Build

Googling says that DropBox uses QtWebEngineProcess, so I paused DropBox sync (my .Rproj is in a DropBox local directory).

This all started suddenly, after I did an RStudio re-install yesterday.
I ran in terminal:
rm -rf ~/library/Caches/RStudio
rm -rf ~/Library/Application Support/RStudio

A closed topic discussed a similar problem, but the fixes therein are not resolving my problem.


Can you provide a reproducible example?