The example's Workflow Note and the Krea 2 Outpaint Model Patch help page
said you could paint over part of the picture with the mask editor and pad
at the same time. Load Image + Pad drops the picture's alpha, its mask
covers only the new padding, and it hides the core preview the mask editor
opens from, so that never worked. Both now say the workflow only extends
the picture outward.
The help page also said a Crop For Inpaint stitcher places the reference
over the full frame. On source rectangle it falls back to where the crop
sat in the full picture, so the page now says to use whole canvas with one.