Starting Firefox 78, the built-in PDF Viewer in Firefox (PDF.js) can be set as default PDF Reader on Windows. Mozilla has made the necessary changes to browser installer to register Firefox as a PDF handler on windows 10.
Like Chrome and Microsoft Edge, Mozilla Firefox also comes with PDF Viewer built-in that displays PDF files inside the browser.
When you install the new Microsoft Edge browser or other Chromium browsers such as Vivaldi, Opera, and Brave they register as a program to open PDF files in Windows 10, which Firefox doesn’t do considering it supports viewing most of the PDF files without a plugin.
Because of this Firefox doesn’t appear in the choose app dialog for PDF file type in the choose default apps by file type page. Now, this has been addressed with the latest Firefox Installer.
The installer is responsible for registering support for default file associations on Windows. We’ve always intentionally left PDF out of that list, but that decision may be changing soon, so I’m moving this bug so that it can find its way into the installer team’s planning.
Make Firefox as default PDF Reader in Windows 10
1. Ensure you’re using Firefox 78 or later, Click on Start > Settings > Apps > Default Apps
2. Scroll down and select “Choose default apps by file type”
3. Scroll down and find .pdf, click on the current default Program icon
4. In the Choose app dialog, select Firefox
5. Open any PDF file on your device, it’ll now open in Firefox browser.
Note: As of today, you need to select “Firefox Nightly”
For the uninitiated, Firefox PDF Viewer comes with following features
- Supports printing
- It allows you to download PDF files to save to your computer.
- Offers Presentation or fullscreen mode
- Display PDF document thumbnails or outlines or attachments in the sidebar.
The PDF.Js is constantly updated by Mozilla with improvements, bug fixes, and new features.
Which web browser or PDF application you’re using for PDF needs on Windows? Let us know in the comments below.
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