Composer compatible version of JpGraph library with PHP 8.1 support
Long story short: https://packagist.org/packages/mitoteam/jpgraph.
We use JpGraph library in several projects. It is looks like abandoned project: almost no updates from maintainers, website and documentation is not updated either. We tried to look for alternative... and there are none! All other charts libraries are either paid ones or have much less functionality. So we stayed with JpGraph.