After Effects 2020 Extensions Not Working - CEP HTML Engine Error

Hello,

Up until recently, whenever I try to use/open an extensions window, I either get an 'CEP HTML Engine' window crash error, or the extension's window disappears, and is then completely blank.
This has happened with every extension I try to open (like Motion Factory, and even Adobe Color Themes).

Currently using AE Version 17.6.0.
Any help would be great!