I'm looking for washable non-slip bathmats for an untextured tiled floor. The ones I have are nice thick memory foam and they have been great.

Still are great actually. The problem is after a few washes over 12+ months they progressively lost non-slip stickiness on the back.

DIY solutions like attaching to those kids sucker grip bath protectors occured to me with nothing easy, durable or perfect yet.