Subject: bug#13949: 24.4.1; `fill-paragraph' should not always put the buffer as modified

From: Eli Zaretskii <[email-masked]>
Date: Sun, 27 Mar 2016 18:58:48 +0300

> From: Óscar Fuentes <[email-masked]>
> Cc: [email-masked],  [email-masked],  [email-masked]
> Date: Sun, 27 Mar 2016 17:29:36 +0200
> 
> AFAIK, a file-visiting buffer is not marked as modified when text
> properties are applied to it. This makes sense, because text properties
> are not part of the contents of the corresponding file.

It is, and they are.  Here, try this:

 emacs -Q
 C-x C-f README RET
 M-: (put-text-property 1 10 'myprop 'foo) RET

Then look at the buffer-modified indication.