Why do online PDF documents have to open in browser window? There is really no useful purpose in opening PDF documents in web browser and this "feature" has many drawbacks:
- The Adobe Acrobat Reader plugin takes ages to start. While it is starting, your browser is frozen and you can’t do anything else.
- When it doesn’t work, it crashes your entire browser, or just freezes it.
- When it works, usual browser shortcuts don’t work, including those to close your window or tab, navigate between tabs, go back and forward, etc.
- There is really no reliable warning when you follow a hyperlink that you are going to open a PDF file. So you hang, crash or freeze without any courtesy notice.
There is a very easy way to change this behavior with Firefox on Windows:
- Go to the "Tools -> Options" menu
- Select the "Content" tab
- Click "File types" manage button
- Enter "pdf" in the "Search" box
- Select "Change Action.."
- Change the selection from "Use this Plugin" to "Open them with the default application", which should point to Adobe Acrobat, Adobe Acrobat Reader, or your favorite PDF viewer

You can also try these solutions:
Uninstall Adobe Acrobat Reader and use Foxit reader which as faster, cleaner and free. You won't find anything that it can’t do that Acrobat Reader can.
Use the PDF Download extension for FireFox as well. Every time you click on a link, checks if the target is a pdf file and in this case let you choose what you want to do (open pdf file inside or outside Firefox, download it to the filesystem or view it as HTML).





