If you thought browser-based Minecraft was just a stripped-down version of the real thing, the modding community for Eaglercraft 1.12.2 is here to prove you wrong.
Cheat/Utility Clients: Various updated "hack" clients (like Resent Client) exist for 1.12.2, providing X-ray, combat enhancements, and movement tweaks. How to Install Updated Mods mods for eaglercraft 112 2 updated
Waypoints and Mini-maps: Mapping mods have seen significant updates, allowing for faster refreshing of the mini-map without causing "micro-stutters" during gameplay. You can now save and export waypoint data to your browser's local storage. Beyond the Browser: The Renaissance of Eaglercraft 1
Built-in PBR Shaders: The EaglercraftX u2 client comes with optimized PBR shaders and texture packs designed specifically for WebGL. Note that standard Java Edition shaders are not compatible due to the underlying web architecture. You can now save and export waypoint data