That does look a little odd.
Have you tried the old eBay tradition of clearing cookies and cache, then restarting the browser? If you allow Flash Player to run (no idea whether it's still available in Edge) you might need to clear your flash cookies, too. This might necessitate entering a security code next time you try to sell - my info there might be way out of date...
You might also check that your antivirus/firewall isn't trying too hard to be helpful - if it's possible to examine its settings and allowed sites etc, then that might offer a clue.
Interesting that Edge seems to have worked fine so far, as it's not on eBay's list of supported browsers.
https://www.ebay.co.uk/pages/help/account/browser.html
Perhaps that makes it even more susceptible to eBay-type glitches.
If nothing else works, why not install Firefox? It's supported by eBay.
(I suppose you could also consider Chrome - as a tinfoil-hat wearer of note, I don't particularly trust it and its strong Google tie-in - but if you're not too concerned about privacy stuff, which is a problem no matter what browser we try to protect ourselves with, it will probably work OK.)
Sorry I can't suggest anything more useful. If you find a solution, perhaps you might post back in case it helps someone else.
