Sometimes when installation companies spray insulation behind your drywall or plaster wall they have to create a small hole the size of quarter to be able to spray the insulation in. Then you are left with a wall just full of drywall repair plugs which have to be treated so they’ll show up at a later date.
In preparation for home painting all the walls first had to have drywall repair to those plaster plugs that filled the holes in. We sanded the plaster patches smoothed to the wall and applied a short piece of plaster tape. In this case we used fiber tape that tape is approximately 2 inches wide and we would cut a 2 inch long. We would stick it on and with some sheetrock 90 compound with plaster over it with a 6 inch blade. We took care not to lay the plaster on too thick (this would create a hump or lump that wouldn’t look good after the home painting was completed. All we did was feather sanded all the edges of the plaster mark. And if there was a little bubble or something inside the plaster mark we would carefully sand that to.