Dynamically skinning means (in yuna's terms) applying skins without restarting.
It is not meant to have the ability to alter stuff on-the-fly with scripting. That's a step further and something else entirely... Nevertheless, it would be a cool addition of course.
But let's first wait on dynamic skinning
After that, we can dream of having stacked skinning, combined script/skin packages, and on-the-fly altering of skins with scripts...
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@gabydday, I have requested your posts (and the replies to it) to be split. Your post is off topic and appears to be a request to skin toasts. But as blessedguy already said, that is already possible (since as long as skinning exists actually). Skinning toasts, and Plus! as a whole, works just the same as skinning Messenger. See the docs....