Disable Firefox PDF viewer If you want to disable the built-in PDF viewer entirely, type, "about:config" in the address bar, then click on the "I'll be careful, I promise!" button.

Default Chrome PDF viewer setting. Click the Start button of Windows. Click Settings. Click Apps. Click Default apps. Search .PDF in search box of set a default app for file type.

You can use the same icon to turn off two-page view mode. To disable this two-page view mode feature, you can repeat the above steps and select Default in the drop-down button for PDF Two-up View ...

Microsoft’s rolling out a new PDF viewer powered by Adobe Acrobat. While the tool will stay free, documents will feature Adobe branding and offer an option to pay for more “advanced” features.

Browse to the PDF you want to display in the message, highlight the filename and then click "Insert." Outlook formats the first page of the PDF and inserts it as a MSO file.

Jacob Salmela shares an Automator action that adds a merge PDF button your right-click menu. To add this menu, you’ll set up a new Automator action (Applications > Utilities), drop in a bit of ...