一段时间以来，我一直在尝试在运行 ubuntu 18.04 的 hp-envy-13 上使用外部显示器。我原以为内核 4.19 会有支持，但似乎仍然不起作用。该适配器（USB-C 转 VGA）在我的 Macbook 上运行顺利，排除了任何电缆/适配器问题，但在 ubuntu 上无法识别。
我在这里错过了什么吗？
$ uname -a
Linux HP-ENVY-Laptop-13-ad1xx 4.19.0-041900-generic #201810221809 SMP Mon Oct 22 22:11:45 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic
$ lspci -d ::0c03 -k
00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21)
Subsystem: Hewlett-Packard Company Sunrise Point-LP USB 3.0 xHCI Controller
Kernel driver in use: xhci_hcd
$ lspci -vt
-[0000:00]-+-00.0 Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers
+-02.0 Intel Corporation UHD Graphics 620
+-04.0 Intel Corporation Skylake Processor Thermal Subsystem
+-08.0 Intel Corporation Skylake Gaussian Mixture Model
+-14.0 Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller
+-14.2 Intel Corporation Sunrise Point-LP Thermal subsystem
+-15.0 Intel Corporation Sunrise Point-LP Serial IO I2C Controller #0
+-16.0 Intel Corporation Sunrise Point-LP CSME HECI #1
+-17.0 Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode]
+-1c.0-[01]----00.0 Alcor Micro Device 6625
+-1c.5-[02]----00.0 Intel Corporation Wireless 7265
+-1d.0-[03]----00.0 Toshiba America Info Systems Device 0116
+-1f.0 Intel Corporation Device 9d4e
+-1f.2 Intel Corporation Sunrise Point-LP PMC
+-1f.3 Intel Corporation Sunrise Point-LP HD Audio
\-1f.4 Intel Corporation Sunrise Point-LP SMBus