See Gnome Web as an example of sizing. I think it's pop-up windows("do you want gnome web to be your default browser") that the WM is trying to handle and all that's needed is a flag check. As for apps not opening, a glance at the logs showed that there needs to be some environment variables set. See XFCE-Terminal as an example. Might be more issues than that so need to test more apps.
See Gnome Web as an example of sizing. I think it's pop-up windows("do you want gnome web to be your default browser") that the WM is trying to handle and all that's needed is a flag check. As for apps not opening, a glance at the logs showed that there needs to be some environment variables set. See XFCE-Terminal as an example. Might be more issues than that so need to test more apps.