This was a few weeks ago, so perhaps it is fixed now. I love that shopstr exists and I'm excited to be a frequent participant there once it's stabilizes a bit.

I just tried to load it (Firefox, Linux) and got

Application error: a client-side exception has occurred (see the browser console for more information).

Deleting all private data in the browser solved this, until I went to orders and now I get it again. Here's some stuff from console, hope it's helpful. After a few refreshes this error disappeared.

NS_ERROR_NOT_IMPLEMENTED: Component returned failure code: 0x80004001 (NS_ERROR_NOT_IMPLEMENTED) [nsIAppStartup.secondsSinceLastOSRestart]

Experiment add-an-image-to-pdf-with-alt-text-rollout has unknown featureId: addAnImageInPDF