(I'm not sure if this is SpamBlacklist or something else, but I'm sure SpamBlacklist people know the right project)
Someone came into #wikipedia-en-help today asking for help with editing https://sh.wikipedia.org/wiki/Milinkovic_Zoran
The edit they were making was adding an external link, so a captcha screen popped up, but they got this view:
{F3263036}
And this in the inspector:
{F3263040}
All of us in -en-help could see the image, and after going to the Special:Captcha/image URL themselves, the user was able to see the captcha on the page. They were accessing the site from Serbia (if that matters) and using Google Chrome. They had restarted the browser and refreshed the page several times.
I'll provide the link to this bug to the user on IRC so they can follow along and potentially further debug the issue if necessary.