📚 Does anyone know if I should worry about that PID 9983?

Hello, sorry if this is not the most suitable sub for this question but I saw something strange today when I logged into the reddit.

A symbol that looks like the number Phi appears on the bottom corner of the screen and very small and half translucent, when I pass the mouse cursor over it, it expands with a long line with several values and appears something like: Rendered by PID 9983 followed by several values and app another value and my country at the end.

I searched about this in duckduckgo and startpage and the only results I found relevant are from subs or reddit users that don't have any posts and only appear in the browser search results. Like that and that. Is this some kind of script I should worry about or is it just some reddit tool itself that for some reason my browser is showing in a different way than expected?

Thanks for your time.