There's a Firefox and Chrome add-on called Disconnect (https://addons.mozilla.org/en-US/firefox/addon/disconnect/) that I disabled and was able to get to the PayPal login. Anyone affected by this happen to use it?

Is Disconnect Premium a VPN? What happens if I already have, or add, a VPN on my device? ↑

Yes, the paid version and the blocking feature of our free desktop and iOS products utilize VPN technology. Because of this, if you already have a VPN, and you want the protections that Disconnect Premium offers, we recommend uninstalling your other VPN and using Disconnect Premium as your VPN. Having another VPN on your device can cause Disconnect Premium to not be able to establish a VPN connection.

Yep that could explain why ;)

My version of Disconnect isn't premium and as far as I knew it wasn't a VPN. I remember downloading it a while back because of some article saying it would speed up browsing and help with privacy. I've never had a problem with it before.

get better!!!!

It was saying the free uses part of it as well.

Would you mind running the wireshark? Don't be afraid, so long you do NOT enter any data in there nobody will kow anything.

As it is just about the redirection.

If we do not see any packages being transmitted it would indicate a browser issue, BUT if there would be packages, that would be something completely different.

And as you do it, as I described earlier, there is really nothing to worry about as the login onto gog would not be capture and so on...Just try not to do anything else, makes the capture better readable ;)

And if you want quicker page display, use like flash blocker and similar. That helps ;)

If you have any privacy concern messages, feel free to PM me ;)

PS: Too all which are having problems, some questions:

1.) Do you use facebook and/or twitter?
2.) Do you use google plus?

Are you connected to any of those services when you try to purchase?

Do you have certificates set to manual or automatic?

Is the connection showing https at the moment? What about when redirecting?

Question for GOG: WHy do I see doubleclick.net in the trace? Prior the connection to paypal?

Is anyone of you having something like killjasmine running? and having the keyword doubleclick in there?

For GOG:

I do see in my trace (working) a quite unusual message:

248 7.021093000 router NIC ICMP 590 Destination unreachable (Fragmentation needed)
252 7.339347000 NIC 23.197.6.253 TCP 1506 [TCP Retransmission] [TCP segment of a reassembled PDU]
254 7.368061000 NIC 23.197.6.253 TLSv1.2 130 [TCP Retransmission] Application Data

All for the moment.....

Sorry, I'm not really in the mood for diagnosing with tcpdumps for game shopping -- usually I get paid for that ;).
Regarding the information you'd get from that dump though, the browser already provides it. The last thing that happens is that the browser PUSHes some json userdata, and then simply nothing.

So, a few people talked about greasemonkey, I only use noscript (with whitelisting for the relevant gog/paypal sites and also completely disabled for testing gog shopping). Could this be a common thing?

I bought Everspace now with Debian Linux 8 and FF 45.3.0 (ESR), Addons: Greasemonkey, ublock, stylish - all active.

Possible help for issue investigation:
Basically:
Firefox 48.0.2
turning add-ons off one by one: unsuccessfull
restarting Firefox in safe mode: successful redirection

Looking deeper:
RequestPolicy (firefox addon) shows requests to fonts.googleapis and googletagmanager
allowing request to fonts.googleapis: fonts changed (obviously)
allowing request to googletagmanager: new request to google-analytics appears
allowing request to google-analytics results in shield icon appearing in address bar
- pressing it and turning tracking protection for site off results in successful redirection

Reasoned guesses:

guess: faulty redirection script.
reason of guess: request to google-analytics appears only after successful request to googletagmanager,
meaning that script indefinitely awaits request response from googletagmanager and then from google-analytics.

guess: blocklist changes.
reason: If redirection script worked fine for some time after "redirection page" introduction
then firefox built-in tracking protection started blocking request to google-analytics at some point because
of blocklist updates.

Hope it would be useful.

Something similar happened to me last week when buying some stuff on ebay. My bank would not allow Paypal to access my account.
When I contacted them I was told that maybe the site wasn't considered safe which I found odd and reccomended I use their MBNET service while they tried to sort it out. One week later and still no word.
One might suspect this is just an excuse to make people use the MBNET service (it creates a virtual card so you don't have to use your real card's data).