No, it is not masking tape but drywall tape. As you may know, drywall comes in sheets that measure 1.4 m x 2.4 m (4 ft x 8 ft). Where the sheets meet, the crack is covered with a plaster called drywall compound and reinforced with a special paper strip. This tape has no adhesive at all and relies on the compound to keep it glued to the wall. When there is not enough compound, or you have heavy condensation on the wall that could release the compound, the tape delaminates. Pry it open with a knife just enough to slide some white glue behind the tape. Hold it in place with masking tape for a day.