If your GPU is Nvidia, that's your problem. The drivers haven't been properly updated for nvidia, and it' looking doubtful that they will.

Also, check your serial on Apple's site. I believe the early 2013 MBPros might be eligible for some free repairs due to some known video issues.

Does it have the additional nvidia graphics card? If so, are you plugged into an external display or running anything that would toggle the graphics card on? By default, it won't be running, so most owners won't notice unless the do some intensive action to enable it

What hardware are you on? High Sierra has some serious issues with older 2012-2014 Macbook Pros that Apple has yet to address.

Those visitors with javascript disabled, by now, expect half the internet to be broken anyway.

admin theme is a mess, code is a mess, and its a glorified blogging platform

It sounds like you really need to check out Craft CMS. I was pretty much in your same exact situation a couple years ago. Craft let's you control everything. You write your own templates, and it doesn't get in the way. Your small but awesomely-worth-it learning curve will be with the twig syntax to output data in your templates. Luckily, it's all really well documented and there's around 4,500 folks on the Slack that can help you out.

It sounds like you're making the very offensive assumption that only women wear panties.

The gigantic community advocating for starched no-wrinkle panties.

This looks great. I signed up on the list. But, tell me you actually have the collect.io domain. If not, I feel like marketing under a different domain is a terrible marketing/branding decision.

This is great, but I'm not sure "parallax" is the right term to use here...?