How do get an html file to open in preferred html application from command line on linux

I usually use the command line tool xdg-mime to determine what applications are associated with a given MIME type.

$ xdg-mime query filetype IMAGE.PNG 
image/png

$ xdg-mime query default image/png
shotwell-viewer.desktop shutter.desktop

You can make this a single command like so:

$ xdg-mime query default $(xdg-mime query filetype IMAGE.PNG)
shotwell-viewer.desktop shutter.desktop

You can change the default using mimeopen like so:

$ mimeopen -d ~/test.pdf

Please choose a default application for files of type application/pdf

    1) E-book Viewer  (calibre-ebook-viewer)
    2) Document Viewer  (evince)
    3) Xournal  (xournal)
    4) GNU Image Manipulation Program  (gimp)
    5) Xpdf PDF Viewer  (xpdf)
    6) Print Preview  (evince-previewer)
    7) Inkscape  (inkscape)
    8) calibre  (calibre-gui)
    9) Other...

use application #2
Opening "/home/saml/Downloads/test.pdf" with Document Viewer  (application/pdf)

NOTE: By the way, the semi-colons are there because there can be multiple associations for a given MIME type. So text/xml could have google-chrome.desktop;firefox.desktop; as it's value would would indicate that there are 2 apps that can handle that particular type.

References

• How to get a list of applications associated with a file using command line
• Is there an "open with" command for the command line?
• xdg-open opens a different application to the one specified by xdg-mime query

I got this to work.

You need to add the key 'StartupWMClass' to your desktop entry.

StartupWMClass: If specified, it is known that the application will map at least one window with the given string as its WM class or WM name hint.

Protocol information here with more details here.

You can install xprop, run it and click the title bar to find out what class your application is.