I have multiple layers that require to center all the boundary layers and change all to the same size.
Is there anyway to select all the layers and adjust it at one go?
You should really learn the Gimp tools, for lining up layers there is the alignment tool.
https://docs.gimp.org/2.10/en/gimp-tool-align.html
and you might use it like this:
https://i.imgur.com/WX6swlP.mp4
However if you go to this post
https://www.gimp-forum.net/Thread-Rotate...ree?page=2 the attachment there contains two scripts and one of them Multiple-Layer-Actions.scm an old script but will do what you require providing the image is not complicated.
edit (Use ofnuts script from your other post for resizing layers - Multiple-Layer-Actions loses transparency)
Edit: forgot that Gimp 2.10 does not automatically add alpha so with Multiple-layer-actions.scm You can to all layers (as three separate applications)
add apha
center all layers
all layers to image size.
Thanks rich,
Didn't know save-all-layers.zip, has two files in it. And "Multiple-Layer-Actions.scm" does resolve my need with these steps you have indicated prior
https://imgur.com/tHzV6NG