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I'm a beginner Mac OS user.

When I open Firefox I receive the dialog below, why doesn't Firefox just start? What is the point of the below dialog?


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up vote 6 down vote accepted

This isn't a dialog, this is the result of mounting (opening) the Firefox.dmg (think of it as an archive or drive image). For mac users it's obvious - you should drag the FF icon to the Applications folder shortcut (the blue folder). This will copy the Firefox application in the /Applications/ folder. Then just unmount (eject) the Firefox.dmg archive and start Firefox from Applications (like you start the rest of your applications).

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…and you can delete the Firefox.dmg (drag it to the trash) after that. :) – Martín Marconcini Jul 2 '11 at 19:26

enter image description here

The file what you downloaded, is an "DMG" archive type (like ISO image).

  • When you double click on it, you open it (called mounted it).
  • After opening the archive you should install the application - simple way - drag and drop into the destination.
  • After the install - eject and usually can trash the dmg archive.
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