Notes about the XPI file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The XPI file type is primarily associated with 'Mozilla/Firefox Browser' by Mozilla.
This is basically a ZIP file that, when opened by the browser utility, installs a browser extension.
To install a local version of the file, you can drag and drop the file onto an open Firefox browser window or use the Firefox File | Open menu command. In most cases the file will be downloaded via Firefox after you've searched for new add-ons and will, at that time, automatically install itself and be available after a browser restart.
This extension applies to both Mozilla and Firefox browsers.
Detailed information for file extension XPI:
File classification: Archive
Mime type: application/x-xpinstallIdentifying characters
Hex: 50 4B 03 04 , ASCII: PK
'Identifying characters' used on FILExt.com are
provided by Marco Pontello from his TrID database
To change file associations press Windows Key
and then Apps and Features
> Default apps
> Choose default apps by file type
Invalid file associations could be the result of underlying issues within your Windows PC.