Found the error Not allowed to load local resource: file:///etc/passwd
while looking at infosec.pub’s communities page. There’s a community called “ignore me” that adds a few image tags trying to steal your passwd file.
You have to be extremely poorly configured for this to work, but the red flags you see should keep you on your toes for the red flags you don’t.
But… why? Why even put that URL there? Even if it was most likely harmless for all users, this still looks like an attempt at data exfiltration.