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Open in Browser Firefox add-on
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Open in Browser

Open in Browser is a Firefox extension that allows you to open documents directly in the browser.


You can install the extension from its page.


Opening Dialog View as Menu


You can add additional mime types to the list by creating a pref named extensions.openinbrowser.additional_mimes in about:config with the list of additional types separated by a |. For instance, application/pdf|audio/ogg-vorbis.

Limitations and Issues

  • It does not work for protocols other that HTTP because of a technical limitation. It is only possible to view the content as source in this case.
  • Automatic opening in browser is not implemented, that's why the "Do this automatically for files like this..." checkbox is greyed out when open in browser is selected.
  • Some users have reported compatibility issues with the "Tab Mix Plus" add-on.

Building the extension

You need a Unix shell with make and git in your PATH. Cygwin works well on Windows.

Go in the root of the sources and run:

make xpi

This will generate a openinbrowser-VERSION.xpi archive in the current directory.

If you want to modify the sources, first commit your changes in git and then run the above make command again. You can use git commit --amend to update the last commit.


A few manual tests are available in the tests directory.

For the HTTP protocol tests, you should serve the tests directory with a Web server that interprets PHP scripts. If you have Docker, you can use the following command:

cd openinbrowser/tests/
docker run -it -p 8080:80 -v "$PWD":/var/www/html php:5.6-apache

which will run a Web server on port 8080. You can then access the tests using http://localhost:8080/tests.html and follow the instructions.

For the file protocol test, open the tests/tests.html file from the file system (for instance. file:///C:/openinbrowser/tests/tests.html) and follow the instructions.

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