So I moved onto Firefox. For starters, I did some tweaking to improve Firefox performance from terrible - to usable. Some things can be tweaked from the settings panel while others have to be enabled from a hidden options list. The very basics can be found in Preferences -> Advanced and:
In general: disable Smooth Scrolling
In Data Choices: disable Firefox Health Report
For the more advanced tweaks one needs to enter about:config in the URL bar. There is a search bar at the top so you can look for the settings I list below.
For starters you may want to make sure to prevent pinch-to-zoom behaviour by setting:
zoom.maxPercent to 100
zoom.minPercent to 100
Then find and set the following:
Its also worth adding the following integers by right clicking anywhere on the about:config page, selecting New -> integer:
Lastly, similarly to Chromium, it’s a good idea to move cache to ram by setting the following:
The last variable can be tweaked; value of 100000 = 100mb RAM. The -1 value, as I understand it, refers to dynamic allocation of RAM usage. I don't know what the optimal setting for this ought to be. Also, you can find out more about how much ram is used and other options by entering about:cache in the browser bar.
Now that faster Firefox performance is improved (subjectively, when running off of eMMC, it’s on par with Chromium in Mate DE) we can move onto enabling playback via VLC player.
The plugin needed to achieve this is called VLC Youtube Shortcut. Extensive instructions are not needed for getting this to work - after installing the plugin, you will be able to just right click the youtube (or other) video in Firefox and select Play Video from link from the drop-down menu.
To get good playback in VLC some tinkering is needed … but that is a topic for a different post.