from the original developers, several community-driven projects and "feature ports" have emerged to bring 1.21 content to the web browser. Current State of Eaglercraft 1.21.1 Experimental Builds : Some developers have released TeaVM ports of Minecraft 1.21.1 on GitHub
Copper grates, tuff variants, and crafters. eaglercraft 1.21 1
For years, the idea of playing a fully functional version of Minecraft inside a web browser felt like a distant dream. Laggy demos, missing features, and severe version lag defined the early days of "browser Minecraft." Then came —a revolutionary project that brought true Java Edition gameplay to browsers using WebAssembly and advanced JavaScript rendering. from the original developers
However, the situation is nuanced: