A cool guide on australian slangs

A Cool Guide on tactical hand signs

A cool guide on spices

A cool guide on hats

I definitely found one

POW!! Reparations please

Life Lesson: Turn around while you can

Are they stupid?

Found another in a boomers group

Black Mould (?) at Kitchen Sink

How do I get rid of this?

We recently removed wallpaper and repainted the walls. Over the course of the next day, this large grease (?) stain appeared. For context, this is in a hallway next to a wooden bannister, so I'm guessing it's some sort of varnish or oil leftover from when they installed the bannister post. The stain has been there for god knows how long, hidden behind wallpaper. Also for reference, after the removal of wallpaper, all walls were scrubbed with soapy water, dried, sanded, them primed and painted. So the stain resisted/went through all of that. I have since googled remedies and tried washing the wall with a vinegar/water solution, then with dish washing liquid water mix, and it hasn't done a thing. What else could I try? Thanks in advance.