so I'm having precisely the issue described here:
I'm using TeXShop 3.58 on a Macbook pro running El Capitain.
Roughly speaking, I'm working on my thesis (currently 80+ pages), and every time I retex my document the memory used (according to Activity Monitor) increases slightly. TeXShop is currently using 11.19 GB (10.54GB of compressed memory). Historically once it gets past 18-20GB or so I get a warning message saying that my computer has run out of application memory, and forces me to force quit certain apps. Quitting texshop fixes this (temporarily), and reopening it reduces its memory footprint to under 1gb at first.
I've tried the suggestion given in the link above (using the command "defaults write TeXShop ReleaseDocumentClasses 0" in the Terminal), but it didn't seem to do anything.
The link above is however 9 years hold now, so I was wondering if there has been any additional progress on this front.