What should I do when I find duplicate or similar questions on the different sections (like emacs.stackexchange.com and stackoverflow.com)?

Examples:

* [How do I open a non-readable file from inside emacs when I opened emacs as a regular user?](https://emacs.stackexchange.com/questions/24546/how-do-i-open-a-non-readable-file-from-inside-emacs-when-i-opened-emacs-as-a-reg/24547#24547) (from emacs.stackexchange.com),
* which is a duplicate of <https://stackoverflow.com/questions/95631/open-a-file-with-su-sudo-inside-emacs> on another section (stackoverflow.com).