xul-ext-lightning suggests a missing package 'latex-xft-fonts'

$ sudo apt-get install xul-ext-lightning
[sudo] password for jaska:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  xul-ext-calendar-timezones xul-ext-gdata-provider
Suggested packages:
  latex-xft-fonts
The following NEW packages will be installed:
  xul-ext-calendar-timezones xul-ext-gdata-provider xul-ext-lightning
0 upgraded, 3 newly installed, 0 to remove and 5 not upgraded.
Need to get 1,280 kB of archives.
After this operation, 6,152 kB of additional disk space will be used.
Do you want to continue [Y/n]?
Get:1 http://archive.ubuntu.com/ubuntu/ oneiric-updates/universe xul-ext-calendar-timezones all 1.0+build1-0ubuntu0.11.10.2 [42.5 kB]
Get:2 http://archive.ubuntu.com/ubuntu/ oneiric-updates/universe xul-ext-lightning amd64 1.0+build1-0ubuntu0.11.10.2 [1,182 kB]
Get:3 http://archive.ubuntu.com/ubuntu/ oneiric-updates/universe xul-ext-gdata-provider all 1.0+build1-0ubuntu0.11.10.2 [55.2 kB]
Fetched 1,280 kB in 1s (1,051 kB/s)
Selecting previously deselected package xul-ext-calendar-timezones.
(Reading database ... 250732 files and directories currently installed.)
Unpacking xul-ext-calendar-timezones (from .../xul-ext-calendar-timezones_1.0+build1-0ubuntu0.11.10.2_all.deb) ...
Selecting previously deselected package xul-ext-lightning.
Unpacking xul-ext-lightning (from .../xul-ext-lightning_1.0+build1-0ubuntu0.11.10.2_amd64.deb) ...
Selecting previously deselected package xul-ext-gdata-provider.
Unpacking xul-ext-gdata-provider (from .../xul-ext-gdata-provider_1.0+build1-0ubuntu0.11.10.2_all.deb) ...
Setting up xul-ext-calendar-timezones (1.0+build1-0ubuntu0.11.10.2) ...
Setting up xul-ext-lightning (1.0+build1-0ubuntu0.11.10.2) ...
Setting up xul-ext-gdata-provider (1.0+build1-0ubuntu0.11.10.2) ...
jaska@lagavulin:~/src/wesnoth 18:31:41 $ sudo apt-get install latex-xft-fonts
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package latex-xft-fonts is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'latex-xft-fonts' has no installation candidate
jaska@lagavulin:~/src/wesnoth 18:31:56 $ apt-cache show latex-xft-fonts
N: Can't select versions from package 'latex-xft-fonts' as it is purely virtual
N: No packages found