I'm assuming you're referring to a YouTube video or a content creator known as "Tuff Client" who posted a video about Eaglercraft in 2021.

But by 2021, the cracks were showing. The original Eaglercraft repo had been DMCA’d twice. The Tuff Client Discord had gone “read-only” after someone leaked a version with a backdoor. Still, that HTML file survived—passed USB to USB, Google Drive to Google Drive, like a forbidden relic.

Because many original 2021 links for Eaglercraft projects were taken down due to DMCA notices from Mojang, the community primarily shares updated versions through active repositories and community hubs.

: It is frequently cited as a high-performance alternative to the vanilla Eaglercraft launcher. Background Context