u/Historical_Lie1688

I have moved into an appartment 6 months ago. I wanted to paint the appartment but due to being super busy, I kept postponing it. Now, that I have the time, I was assessing the walls to see what I will need. However, I came across this part where I saw shallow written in the platster. I did not understand what does it mean, but it looks suspicious. Should I be worried, and what should I do?