Hi @cat500,
OK I gave you developer access to the support fork and you should be able to browse the repository now. The problem is that on some browsers on some computers the WebGL-only rendering that PsychoJS relies on by default is unavailable.
The fix is to manually edit ‘index.html’ to bring in the ‘pixi.js-legacy’ package. In particular, one needs to replace line 21 to read:
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/pixi.js-legacy@5.3.3/dist/pixi-legacy.min.js"></script>
Please let me know if you need more support, x