Here is a small selection of add-ons for Firefox that improve your downloading experience further. This is useful if you run into issues when a file type is associated with a program that cannot open it correctly, or that is not installed anymore on the system. You can modify the default association in the menu. It is only available for select file types. pdf viewer or HTML5 media player, to play or display contents right in the Firefox web browser.
This displays the standard download dialog where you can select to save or run the file. The following actions are available for each file type individually:
Here you find listed all known file types / mime types. Scroll down to Applications on the preferences page.
Press the Alt-key on your keyboard to open the menu toolbar.