Insync 3.3.2 won’t start on a fresh install of Fedora 33 Desktop Xfce spin.
cat ~/.config/Insync/out.txt qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found. This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem. Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.
Thanks to this thread, I was able to get insync working on Fedora 33 Xfce spin.
sudo dnf install xcb-util-renderutil xcb-util-image xcb-util-keysyms xcb-util-wm libxkbcommon-x11
Now it starts.