how can i limit the canvas to what i see? when i'm blending and painting the brush picks up white color from outside the canvas

how can i fix this?

thanx

You can't. Krita just automatically resizes the layer to where you paint, otherwise a lot of compositional stuff can't be done with Krita.

would be nice to see this as a choice instead because i can't paint freely because of this and i spend too much time fixing problems created by this

very annoying and time consuming