Well, if you browse ebay with Tor Browser, you don’t need javascript (just
close the annoying popup) but if you need to see somebody’s ebay-shop, or
if you want to buy something you need javascript.
I use TB just to browse but I guess I’ll need to use Abrowser to register
or login in order to buy something.
Using Firefox, I block all cookies and use Self-Destructing Cookies to allow
them on a very few websites, I don’t bother about User Agent because I see
no point in servers registering billions of Windows NT desktop.
Instead I use uMatrix to block scripts and frames by default.
As for fingerprinting, don’t forget CSS Canvas (Apple be cursed for this
CSS element) can spy on you as well. You can use CanvasBlocker or forbid CSS
on websites you don’t trust. Actually, blocking images, CSS and scripts
makes websites lighter but sometimes totally blank.
I’m at a loss how to preserve some shades of privacy on ebay. I suppose you
need to tell them your real name and address if you want to buy something,
and then you need to do the same thing again if you need to pay through
Paypal.
The only workaround I thought of, which is rarely possible, is to spot a
vendor you can trust, go to their actual website and order from there, even
phone them, order and send a check.
Ebay and AlixExpress are difficult to avoid, especially for computer or
electronic stuff.