fa3f9bcaee
While it doesn't make sense for window list positions to be truly persistent like dash items, some persistence is desirable. Otherwise any manually set position is lost when the extension is disabled, for example when locking the screen. To address this, serialize the positions as runtime state on drop, and restore them when populating the list. Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/338>