Blend Layer Size Mode
blend-size
Makes the blend layer image inherit the picture’s own sizing. The only valid value is inherit, which applies the request’s w, h, fit and crop to the layer image.
Aliases: blendsize, bs.
Use blend-size[N] to target a specific blend layer, where N is 0–3. Layer 0 is either the bare blend-size or blend-size[0]; if both are supplied, the bare name wins.