I discovered it while trying to connect my website to MySites.guru service. This was my problem:
I'm having trouble with the one Joomla 4 website I've added to MySites.guru - Restaurant Pro. When I click the "Launch Admin Console" links, it shows the usual "One moment please..." screen, but then goes to
https://restaurantprowebsites.com/plugins/system/bfnetwork/bfnetwork/bfAutologin.php with a blank screen. If I copy the URL from the address bar, it is https://Ud6VaR8yF8VXp4Sy:%5E9HafSek%5EU%23%2A84%24L@restaurantprowebsites.com/plugins/system/bfnetwork/bfnetwork/bfAutologin.php.
On all other websites in MySites.guru (all Joomla 3), when you click the Launch Admin Console link, it will automatically log into the password-protected /administrator folder, then log into Joomla backend.
I reported this to MySites.guru and Phil Taylor did some tests. That's when he found the EasyBlog error I reported to you. Somehow that interferes with MySites.guru functionality. Phil deployed a work-around but it still won't automatically log into the /administrator folder. I had to remove that password protection so it will login to Joomla backend.
I thought it would be helpful to report this issue to you so others don't experience the same issue.