- 1). Open Firefox and navigate to the Adobe Reader download page.
- 2). Click the yellow "Download Now" button and save the file to your hard drive.
- 3). Close Firefox after the file finishes downloading.
- 4). Open the downloaded file to launch the Adobe Reader Installer. Allow the files to extract fully, agree to the license agreement and follow the on-screen instructions. Restart the computer to finish installing the Reader software on your system.
- 5). Launch Firefox again.
- 6). Click on the Firefox button in the upper-left corner of the window. Click on "Options."
- 7). Open the "Applications" tab in the new window. Locate "Adobe Acrobat Document" in the list of content types.
- 8). Click on "Adobe Acrobat Document," then click on the drop-down box that appears after you highlight the file type. Choose "Use Adobe Acrobat (In Firefox)" to enable Firefox to read PDF files in-browser.
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