Yet another Matrix Implementation
Pretty old and bloated JavaScript code -- be aware that this monolithic beast could make your computer explode.
It could look like this, that or sth. else...
Actually, these bunch of files comprise a so-called "Plasmoid" -- a term mainly (and hardly) used during the KDE/Plasma 4 era. Nowadays you would rather call it widget.
Whatsoever, even though it is thought to be used as a widget from the Desktop (right away), you could also call it via an ordinary web browser. (Well, at least a subset of features -- see links above.)
For even more information (screenshots, installation instructions and so on) take a look at the KDE store!