Unifying file managers' right-click menu interfaces

[PCMan]

Sorry, I have another idea:
[Desktop Action] groups should also allow the X-KDE-Submenu key, so
creating submenu for submenus is possible. Although there is no real
use case now, this might be useful in the future once someone needs
it.

Also, there might be a new key named Dynamic.
The key contains a command line which can generate menu content dynamically.
After calling the command, its stdout should be inserted to current
desktop entry file.
So we can support dynamic menu items generated with scripts.
This partially solves my preceding question, how to generate menu
according to different context for files of the same mime-type.

Example of its usage:
1.you can use a shell script to examine the content of the folder, and
then generate the menu according to its content.
2.this can be used to develop integration with version control systems.
3.and more....