Thanks for your post and apologies to hear you're having an issue accessing Sky Sports via Firefox.
Make sure you have registered the device via Firefox.
You can manage the devices you have registered for use with the Sky platform by going to anywhere.virginmedia.com > My Profile > Sky Movies & Sky Sports. Delete the current registration and also delete the cache and cookies on your browser.
Once you've done this open up a new Firefox page and navigate to the Sky Sports website. Log in after clicking on the VM logo and attempt to stream.
Let me know how you get on.
Kath_F Forum Team
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