Landscape target layers, must use same size image as terrain size?


when importing an image to work as a mask for landscape texture layers, if i use a smaller resolution map than the terrain size, unreal does not present me with an option to stretch the texture to fit.

I.e. the terrain is 4033, but i don’t need to necessarily use 4033 masks to tell grass textures where to go. But when importing a 1k mask texture, unreal does not make it stretch to fit the 4033 terrain.

Anything can be done about that?

First image: importing a file to work as a mask

Unreals warning, but offers no alternate options:

Third image: after imported a 1k image, it occupies 1km of the terrain and pads the edges.