x@center:/opt/work/opencv/build$ cmake-gui QStandardPaths: wrong ownership on runtime directory /run/user/0, 0 instead of 1000 MoTTY X11 proxy: Unsupported authorisation protocol qt.qpa.screen: QXcbConnection: Could not connect to display localhost:11.0 Could not connect to any X display. x@center:/opt/work/opencv/build$ sudo cmake-gui [sudo] password for x: QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root' MoTTY X11 proxy: Unsupported authorisation protocol qt.qpa.screen: QXcbConnection: Could not connect to display localhost:11.0 Could not connect to any X display. x@center:/opt/work/opencv/build$