I have a my personal application (~/bin/launch-app) that read a text

file with .app extension (myapp.app) and run some stuff of things 

Since the myapp.app is a text file ...

   [lesca@dodo tmp]$ file myapp.app

   myapp.app: ASCII text

if I try bind this file to my program launch-app via nemo, nautilus,

thunar, ecc or via line command mimeopen, all other text (text/plain)

file (es some.txt) are bind to my program.

   [lesca@dodo tmp]$ mimeopen -d /tmp/myapp.app

   Please choose a default application for files of type text/plain

                                           ^^^^^^^^^^^^^^^^^^^^^^^^

   	1) launch-app  (userapp-launch-app-LF774Z)

   	2) LibreOffice Main  (libreoffice)

   	3) Geany  (geany)

   	4) ....

How to bind only .app file to my application?

Many thanks

Found here:

https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/desktop_migration_and_administration_guide/file_formats

Thanks

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