我正在按照这个教程配置Xvfb以无头方式运行firefox。
http://www.alittlemadness.com/2008/03/05/running-selenium-headless/
我目前正在docker镜像（ubuntu:latest）中运行这些命令，以便在创建容器之前检查是否可以正确设置我的配置。
我卡在运行这个命令上：
Xvfb :99 -ac
运行命令后，我得到了以下错误：
Initializing built-in extension Generic Event Extension
Initializing built-in extension SHAPE
Initializing built-in extension MIT-SHM
Initializing built-in extension XInputExtension
Initializing built-in extension XTEST
Initializing built-in extension BIG-REQUESTS
Initializing built-in extension SYNC
Initializing built-in extension XKEYBOARD
Initializing built-in extension XC-MISC
Initializing built-in extension SECURITY
Initializing built-in extension XINERAMA
Initializing built-in extension XFIXES
Initializing built-in extension RENDER
Initializing built-in extension RANDR
Initializing built-in extension COMPOSITE
Initializing built-in extension DAMAGE
Initializing built-in extension MIT-SCREEN-SAVER
Initializing built-in extension DOUBLE-BUFFER
Initializing built-in extension RECORD
Initializing built-in extension DPMS
Initializing built-in extension Present
Initializing built-in extension DRI3
Initializing built-in extension X-Resource
Initializing built-in extension XVideo
Initializing built-in extension XVideo-MotionCompensation
Initializing built-in extension SELinux
Initializing built-in extension GLX
[dix] Could not init font path element /usr/share/fonts/X11/cyrillic, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/100dpi/:unscaled, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/75dpi/:unscaled, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/Type1, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/100dpi, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/75dpi, removing from list!
我通过谷歌搜索找到了一个博客，提到了这些错误：
http://veeraramkumar.blogspot.com/
我运行了这些命令：aptitude install x11-xkb-utils
aptitude install xfonts-100dpi xfonts-75dpi xfonts-scalable xfonts-cyrillic
aptitude install xserver-xorg-core
然而，该命令：
aptitude install xfonts-100dpi xfonts-75dpi xfonts-scalable xfonts-cyrillic
给出此错误：
No candidate version found for xfonts-100dpi
No candidate version found for xfonts-75dpi
No candidate version found for xfonts-cyrillic
No candidate version found for xfonts-100dpi
No candidate version found for xfonts-75dpi
No candidate version found for xfonts-cyrillic
The following NEW packages will be installed:
xfonts-scalable
然后它成功安装了xfonts-scalable。现在当我重新运行命令时：
Xvfb :99 -ac
我只收到这些错误（降至5个错误）：
[dix] Could not init font path element /usr/share/fonts/X11/cyrillic, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/100dpi/:unscaled, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/75dpi/:unscaled, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/100dpi, removing from list!
[dix] Could not init font path element /usr/share/fonts/X11/75dpi, removing from list!
我尝试使用apt-get查找xfonts-100dpi、xfonts-75dpi和xfonts-cyrillic软件包，但它也表示这些软件包没有安装候选项。我需要安装哪些适当的软件包才能正确配置Xvfb以无头模式运行Firefox？或者我应该做些其他事情吗？
谢谢。