Max Nikulin <manikulin@gmail.com> writes:

> On 21/05/2022 08:44, Ihor Radchenko wrote:
>> Max Nikulin writes:
>> 
>>> It is the same with and without -Q and no, I have not customized
>>> `mailcap-user-mime-data', its value is nil, easy customization interface
>>> tells that it is the standard value. There is a chance that debian has
>>> some patch, but most of debian specific is disabled when -Q option is used.
>> 
>> Interesting. In any case, it confirms that mailcap behaviour depends on
>> both Emacs settings and also system settings.
>
> You should be even more surprised, if I say that [[file:~/tstorg]] link 
> is opened in emacs buffer in shell-script mode (emacs-27.1, org main 
> HEAD) despite
>
>     (mailcap-mime-info nil)
>     nil

>
> The source of the problem is that Emacs-27 was released with the 
> following bug:
>
> https://debbugs.gnu.org/cgi/bugreport.cgi?bug=40247
> mailcap-mime-data erased when parsing mime parts
>
> So `mailcap-parse-mailcaps' called from `mailcap-mime-info' erases 
> predefined associations in Emacs-27.

If I understand correctly, this extra complication does not affect most
of the systems. I am not sure if we need to work around it.

Also, I am attaching a patch to address the original issue. We can just
use file command when available. WDYT?

Best,
Ihor