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Dear freesurfer experts, recently I update freesurfer to freesurfer 7.4.0 under Ubuntu 20.04. when I try to launch freeview, I get error message as:

freeview 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, webgl, xcb.

Abort (core dumped)

could anyone can direct me how to solve this problem ? sincerely Jung Lung Hsu