Why does my PDF download instead of opening in Firefox?

Question

Why does my pdf download instead of open for viewing in Firefox?

Answer

Here’s how to troubleshoot some problems in the new Firefox PDF reader:  https://support.mozilla.org/en-US/kb/view-pdf-files-firefox-without-downloading-them#w_using-a-pdf-reader-plugin

The section of the help article that opens will show you how to change the settings to use Adobe Acrobat or Reader instead of the built-in PDF reader.