I cannot post in this Forum using Firefox

Hi cocoon,

This happens inside and outside Sandboxie?
Have you tried clearing the cache?
Are you behind a firewall/vpn? If yes, please disable it and re-test. 
Are you using any blocker extensions, or any extensions at all? (If so, which ones, and can you try disabling them and re-test?) 

Regards,

Hi cocoon,

This happens inside and outside Sandboxie?
Have you tried clearing the cache?
Are you behind a firewall/vpn? If yes, please disable it and re-test. 
Are you using any blocker extensions, or any extensions at all? (If so, which ones, and can you try disabling them and re-test?) 

Regards,

I tried clearing the cache, cleared the cookies for the Sophos domain, accessing the forum outside the sandbox, but still no luck.

There is no firewall other than whatever Bitdefender provides. No VPN.

I use Ublock origin, but I disabled it, again with no success.

As I wrote before, Microsoft Edge works fine. Anyway, I notice the problem only with Firefox and the Sophos forum (so far).

EDIT: I created a new sandbox and now I believe the problem with posting to this forum has been solved. I don't understand why, given that I had deleted the previous sandbox contents several times before.