A holder for plastic scrapers like https://www.amazon.com/dp/B09Y5WQFP4 or numerous other identical ones.
There are two models, the 2x3 is a very tight fit and suitable for use on a wall. It does remove just a small bit of the top hole walls, but they should still be usable and functional.
The 2x4 is a much looser fit, has chamfered sides, and works great for a drawer. It also has a small amount of storage for blades.
If you want more blade storage, one of my other models is just that.
Models are on OnShape if you would like to modify.