[xcb] Unknown sequence number while processing queue [xcb] Most likely this is a multi-threaded client and XInitThreads has not been called [xcb] Aborting, sorry about that. Cities.x64: xcb_io.c:269: poll_for_event: Assertion `!xcb_xlib_threads_sequence_lost' failed. Stacktrace: Native stacktrace: /home/owen/.local/share/Steam/steamapps/common/Cities_Skylines/Cities_Data/Mono/x86_64/libmono.so(+0x91f55) [0x7fec5937ef55] /usr/lib/libpthread.so.0(+0x1386f) [0x7fec6979c86f] /usr/lib/libc.so.6(gsignal+0x142) [0x7fec69277d22] /usr/lib/libc.so.6(abort+0x115) [0x7fec69261861] /usr/lib/libc.so.6(+0x26746) [0x7fec69261746] /usr/lib/libc.so.6(__assert_fail+0x45) [0x7fec69270615] /usr/lib/libX11.so.6(+0x40d2c) [0x7fec68fc7d2c] /usr/lib/libX11.so.6(+0x40dc7) [0x7fec68fc7dc7] /usr/lib/libX11.so.6(_XEventsQueued+0x81) [0x7fec68fc8181] /usr/lib/libX11.so.6(_XGetRequest+0x55) [0x7fec68fcb175] /usr/lib/libX11.so.6(XNoOp+0x24) [0x7fec68fb6394] /usr/lib/libGLX_mesa.so.0(+0x306e2) [0x7fec65b9e6e2] /usr/lib/libGLX.so.0(+0x1b427) [0x7fec690e3427] ./Cities.x64(X11_GL_CreateContext+0x288) [0x1421540] ./Cities.x64(SDL_GL_CreateContext_REAL+0x54) [0x13be7da] ./Cities.x64() [0x1266b20] ./Cities.x64() [0x12652b8] ./Cities.x64() [0x1265368] ./Cities.x64() [0x1235a8b] ./Cities.x64() [0x454e83] /usr/lib/libc.so.6(__libc_start_main+0xd4) [0x7fec69262b24] ./Cities.x64() [0x45e048] Debug info from gdb: ================================================================= Got a SIGABRT while executing native code. This usually indicates a fatal error in the mono runtime or one of the native libraries used by your application. =================================================================