Re: Suggest installing more fonts?

[Stefan Monnier]

> I think, over the years, the most common question users have that has an
> easy-to-fix solution is: "Why is Emacs displaying boxes for some of
> these characters I'm seeing?"  The solution is "install some more
> fonts", of course.

[ FWIW, I don't think replacing those tofu chars with some "ugly
  default" is a good option: it's more work with very little benefit if
  any, since the problem still remains largely unchanged.  ]

I think to solve this problem we need to have a clear idea of what the
users do when they're faced with this:

- Does the problem only affect Emacs and not other applications?
  If so why?  If not, then what do other applications do about it?
- Do users immediately run to search the internet for answers without
  even trying to interact any further with their Emacs instance to
  investigate the problem first?
- If they do interact with Emacs, what do they do?  Do they move the
  mouse over the tofu?  Do they look for some help some other way?

The potential elements of solutions can be:
A- Make the users understand that the problem is a lack of fonts
B- Steer the users to the appropriate fonts
C- Fix the problem that makes Emacs fail to find the fonts when other
   applications deal with it just fine.

We could arrange for some kind of tooltip to show up when you wave the
mouse over those tofu chars, but that won't help if the users don't pass
the mouse over them.

We could have the redisplay code record the tofu chars and their
location in some global var, and then use something like
`post-command-hook` to popup a help/warning buffer explaining the
problem and its potential solutions.
That could be annoying for experienced users, tho, so it should come
with a "don't warn me again" button.


        Stefan