Show us the issue. Is it a password issue or you cannot get to the site. I can get to it in Water and Firefox. see screenshots

No, not a validation issue, when I click on the url I get the circular icon spinning which never resolves. If I copy the url and paste it into one of the other browsers I immediately resolves to the site. So it is a Firefox problem

Never resolves... When I click on the url, it resolves for me. Who are you using for DNS?

Since you mentioned it I was using Cloudflare but tried Google and router but no change. I am using Firefox 97.01(64-bit)

So the issue was ghostery. If you are able to access this site, mark this as resolved.

I have found that the addon Ghostery was the the culprit. What annoys me is that even in the app it did not give any indication of the problem but disabling it allowed access to the website. It confuses me that Barclays is the only website affected. A permanent solution was to mark the website within the app as "trusted". Thanks for your help now mark as resolved.

I have this problem. When I try to login to Barclays Bank at https://bank.barclays.co.uk/olb/authlogin/loginAppContainer.do

I get the response:

"Bad request Your browser sent a query this server could not understand. "

Disabling all addons (Facebook container & Ad Blocker) makes no difference.

This has been going on for a while now. Previously (6months ago?) I could login but not get any of my account data.

The site works fine in Edge.

The site does not work for me until I disable Ghostery. see screenshots Did you run Firefox in Safe Mode or did you just disable those 2 add-ons? Any more add-ons? Post a similar screenshot. https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf