I asked this some time ago under another topic, but my question has had no views but my own (at least, I notice that it changes after I've dropped in, so I think I'm the only one looking at it), so I'm trying under another topic in the hopes that somebody will see it. I manage several accounts for my employer. Just recently a couple of them are having issues with the address field no longer automatically populating when I use the "Reply" function. It doesn't happen on every email, but I'm spending enough time having to copy-and-paste addresses from the header back to the address field that it's becoming a hindrance. I don't see a pattern in the types of emails that happens with - all our emails come through our zerolag server, and the individual customer email addresses are all over the place - some come through gmail, some are Yahoo, many are private domains, etc. I do notice that if I reply to one email from a particular person and the field doesn't populate, then none of them to that person will. I've started TB in Safe Mode, disabled all Add-ons (I only use three) and seen no difference. None of the Add-ons have recently updated. I'm using version 52.9.1(32-bit) on Windows 10.