bde974087a
As per design discussion, the first page is a somewhat of a special page where we really don't want to change anything unless necessary. Append new icons at the first available slot after the first page. Make the placeholder icon be appended to the first available page as well, since it's always used when dragging from folder dialogs. https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1284