How to improve XVFB display quality

I am currently running chrome on AWS Linux servers with this [Puppeteer and XVFB setup](https://github.com/nsourov/Puppeteer-with-xvfb) . I also built a little chrome extension that handles the recording with *MediaRecorder* and *chrome.tabCapture*. It's basically meant to spin up chrome on the server and record a video of a specific page. To get a virtual display on the server, I've had to use XVFB. I just hit a little block on video quality. It doesn't get as clear enough even after increasing the bitrate as high as 11mbit/s. Screen resolution is 1920x1080. I'd appreciate some pointers/tips on how to improve the quality from the XVFB side. PS: The typical server I'm running this on has 4 vCPUs and 16gb memory.