This is a strange problem: There are two websites (a bank and a healthcare provider) that I can access using Firefox ESR or Chromium on Linux (OpenSUSE Leap 15.0).
But just starting a few weeks ago, I cannot log into these sites using my OpenBSD 6.4 machine. I could log in last month, but I am not able to log in now. I have tried both Firefox ESR and Iridium on OpenBSD. I've tried changing my user agent string. I've also deleted all of my browser preferences, but I still cannot log in. In one case, the website prints an obscure error message after I enter my password. On the other website, each time I enter my password it asks me to log in again, without any error message. I've contacted the website administrators of one site, and they're clueless. I have not changed anything on my OpenBSD machine within in the last month. But one of the websites has updated its appearance within the last month. So, these websites appear to have made some sort of change that causes this problem on OpenBSD, but not on Linux. Is anyone else seeing this behavior?