再会，
我在 2013 款 MacBook Pro 上运行着 ubuntu 18.04。
这款 Mac 型号左侧有两个雷电 2 端口。
一个端口运行正常；但是，另一个端口（最靠近屏幕）却出现故障。
Ubuntu 正在识别该端口上的显示器（HDMI 适配器），但显示器上没有显示任何内容。
相同的显示器和适配器在另一个端口工作正常。
有什么办法可以解决这个问题吗？我尝试使用 xrandr 将其设置为镜像模式（如此处的其他帖子中所示），但这也不起作用。
以下是插入 HDMI 设备时 xrandr 的输出：
root@UbuntuBook:/etc/X11# xrandr -q
Screen 0: minimum 320 x 200, current 3840 x 1080, maximum 8192 x 8192
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 331mm x 207mm
2880x1800 59.99 +
2880x1620 59.96 59.97
2560x1600 59.99 59.97
2560x1440 59.99 59.99 59.96 59.95
2048x1536 60.00
1920x1440 60.00
1856x1392 60.01
1792x1344 60.01
2048x1152 59.99 59.98 59.90 59.91
1920x1200 59.88 59.95
1920x1080 60.01 59.97 59.96* 59.93
1600x1200 60.00
1680x1050 59.95 59.88
1600x1024 60.17
1400x1050 59.98
1600x900 59.99 59.94 59.95 59.82
1280x1024 60.02
1440x900 59.89
1400x900 59.96 59.88
1280x960 60.00
1440x810 60.00 59.97
1368x768 59.88 59.85
1360x768 59.80 59.96
1280x800 59.99 59.97 59.81 59.91
1152x864 60.00
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 521mm x 293mm
1920x1080 60.00*+ 50.00 59.94
1680x1050 59.88
1600x900 60.00
1280x1024 60.02
1440x900 59.90
1280x800 59.91
1280x720 60.00 50.00 59.94
1024x768 70.07 60.00
800x600 72.19 60.32 56.25
720x576 50.00
720x480 60.00 59.94
640x480 72.81 66.67 60.00 59.94
720x400 70.08
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
HDMI-3 disconnected (normal left inverted right x axis y axis)
注意：我没有双重启动，所以我无法知道它是否在 MacOS 端运行。