It is now 2020, and the WebOS browser in LG Smart TVs (which I believe is Chromium-based) is still massively out of date and doesn't work properly with a ton of websites!
The main problem is actually very simple. The browser doesn't support EMCAScript 2015 or ES6.
Basically, translated from nerd speak, it doesn't work properly with modern code using new features created since 2015, so any newer websites will break unless they've been written to be compatible with ancient browsers and OSes.
This should not be the case on a TV made in the current year. It should be running an up-to-date web browser, if not for convenience, then for SECURITY reasons as well!