On Tue, 12 Nov 2019 09:28:15 -0500, Dennis Lee Bieber
 declaimed the following:

>NOTE: I'm still running the default file manager for Raspbian, which I
>believe is Thunar. Don't know if the one you are running will behave the
>same way.

 Whatever it is, it is different from the behavior of Debian under xfce
(my VirtualBox image). Under xfce the right-click menu shows the default
opener, and the open-with submenu has a section of "recommended"
applications, followed by a listing of all applications on the system.

 In experimenting, I managed to locate (this is Debian)
-=-=-
wulfraed@debian:~$ cat ~/.config/mimeapps.list
[Added Associations]
text/html=firefox-esr.desktop;
text/plain=mousepad.desktop;
text/x-python=python3.7.desktop;gvim.desktop;code.desktop;
x-scheme-handler/http=exo-web-browser.desktop
x-scheme-handler/https=exo-web-browser.desktop
x-scheme-handler/mailto=exo-mail-reader.desktop
application/xml=gvim.desktop;
text/x-scheme=gvim.desktop;
application/vnd.kde.kxmlguirc=gvim.desktop;

[Default Applications]
text/x-python3=gvim.desktop
text/x-python=gvim.desktop
wulfraed@debian:~$
-=-=-

(and on Raspbian)
-=-=-
pi@rpi3bplus-1:~/.config$ cat ~/.config/mimeapps.list
[Default Applications]
text/x-python3=Thonny.desktop
text/x-python=Thonny.desktop
text/plain=gvim.desktop

[Added Associations]
text/x-python3=Thonny.desktop;gvim.desktop;userapp-python3.7-9AM0A0.desktop;
text/x-python=Thonny.desktop;gvim.desktop;
text/plain=gvim.desktop;
pi@rpi3bplus-1:~/.config$
-=-=-

 Which leads (Google) to
https://wiki.archlinux.org/index.php/XDG_MIME_Applications#mimeapps.list

 Hand editing the mimeapps.list files might be faster than piecemeal
"set default" applications. Also, the "set default" action is per user (the
above sample files), but you could edit a global file.

NOTE: Debian/Raspbian appears to use /usr/share/applications/mimeinfo.cache

... and editing
pi@rpi3bplus-1:~$ sudo vim /usr/share/applications/mimeinfo.cache

did NOT adjust the menu order... only the ~/.config/mimeapps.list seemed to
affect the ordering.


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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