Support holding alt while invoking modifier operations for add, apply,
remove, and move to index in the property editor. This affects all selected
editable objects instead of just the active object.
Though the alt key is not that visible, it's consistent with the
existing multi-object property editing shortcut. If/when multi-
object editing is every made the default, the alt key could
be reversed here too.
Changes as part of #120230.
Pull Request: https://projects.blender.org/blender/blender/pulls/120695
9a7f4a3b58