[xmonad] Add 'browser' to XConfig

[Bruce Stephens]

gwern0 at gmail.com writes:

> So I was recently contemplating my xmonad.hs
> (<http://haskell.org/haskellwiki/Xmonad/Config_archive/Gwern's_Config.hs>)
> and wondering whether my XMonad.Actions.Search and other extensions
> were yet in their ideal form, and it occurred to me: why do I have
> to keep writing "firefox"? I even have a shortcut defined, 'ff',
> which I use at least 8 times.
>
> Why am I constantly supplying Firefox as a parameter? Well, the
> answer is that those functions *need* a browser to use, they can't
> get away with getting it from somewhere else. There is no somewhere
> else, as there is no POSIX standard way of letting a user define a
> preferred browser (yes, I know about Debian's x-www-browser stuff,
> but that's Debian, and I know about environmental variables, but I
> don't think there's any standard $BROWSER like there is $HOME or
> $EDITOR).

Not from lack of trying, <http://catb.org/~esr/BROWSER/>.

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