Improve "Total Blocking Time" in WebGL

I’ve recently been trying to convert my mobile app to the browser using WebGL. It’s been going great and easier than I thought but I’m this close to perfection.

There is a tool in most common browsers called Lighthouse. This tool will help you analyze/improve your website. Normally you strive to always get 100/100/100/100 on performance, accessibility, best practices, and SEO. My current scores are 83/100/100/100, whereas my performance is 83. The thing that’s causing this is the “Total blocking time” (see image)

Is there a way in Unity to improve this number and be able to get that sweat 100/100/100/100?

Some of the things I already do are:
Texture compression: default format (DXT)
Code optimization: Size (for faster load times)
IL2CPP Code Generation: Faster (smaller) builds
Enable Exceptions: Explicitly Thrown Exceptions Only (if I set this to none it will crash the game)
Compression Format: Gzip
Debug Symbols: Off
Decompression Fallback: true (otherwise my game wont run because of gzip)