Veterans will be happy to hear that have been fixed. While not perfect to 1.8.8 vanilla standards, it is close enough to build a working piston door or a simple item sorter.
Ensure your browser has hardware acceleration enabled in its settings to let your GPU do the heavy lifting. A Note on Safety and Legality eaglercraft 120
Eaglercraft 1.2.0 represents a technical marvel—a successful attempt to bring legacy Java Edition Minecraft to the browser. It allowed students and players with low-spec hardware to access the game. However, due to copyright infringement, the project is no longer legally distributed. Veterans will be happy to hear that have been fixed
If you meant in Eaglercraft: That does not exist officially. The latest stable port is roughly equivalent to Minecraft 1.12.2. due to copyright infringement