Hi, just developped this little addon to be able to check all GP materials in a project from one place, and setup them quickly !
I currently work on a project where i often build without worrying about colors, and at the end, when i have the final composition, i readjust all of them. My scene is composed of separate Grease pencil objects, so i have to select them one by one to set them up, and i can’t copy paste color from one to another in a simple manner.
With this little addon, you have a new N-Panel (by default in Grease Pencil category) which shows you important settings of selected objects materials.
You can also search for the popup operator through the search menu, and assign it a shortcut or to quick favorites (its id is gp.material_inspector_popup).
Hope it could be useful for others, Cheers !