Unable to view or print packing slips or invoices when using Firefox

[brian_mk]

When using Firefox, if you click on the link to create a packing slip or an invoice, you just get a blank page.

The example below shows what happens for an invoice.

I have uBlock Origin installed on Firefox but it is disabled for eBay.

It works as expected when using MS Edge.

I have not tried Chrome.

[brian_mk]

This is what you get if to try to print a packing slip:-