On Monday September 25th from 10PM EDT - 12AM EDT (2AM UTC - 4AM UTC on September 26th), we will be performing system maintenance on the Firefox Accounts databases for two hours. During the maintenance window, there will be brief periods of a few minutes where users will not be able to login to their accounts. Please try again at a later time.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Firefox suddenly won't display PDFs in browser window.

  • 2 replies
  • 1 has this problem
  • 1890 views
  • Last reply by cor-el

Will-S
Will-S
more options

For years, I've clicked on PDFs online and they've opened in a browser window. Then, if I wanted a copy, I downloaded it. Suddenly, this doesn't happen. It doesn't open, it just goes straight to download. I've changed no settings. Other browsers open the PDFs in question. What happened and how do I fix it. I'm running Firefox 78.0.2 (64-bit) on a 2017 iMac running 10.14.6. Thanks.

For years, I've clicked on PDFs online and they've opened in a browser window. Then, if I wanted a copy, I downloaded it. Suddenly, this doesn't happen. It doesn't open, it just goes straight to download. I've changed no settings. Other browsers open the PDFs in question. What happened and how do I fix it. I'm running Firefox 78.0.2 (64-bit) on a 2017 iMac running 10.14.6. Thanks.

Chosen solution

It sounds like maybe you have accidentally changed the default PDF program that Firefox uses. If you go to the Firefox settings page and scroll down to the Applications section, you should see the Portable Document Format (PDF) content type listed there. You can change the default action to Open in Firefox if you want Firefox to load the PDF instead of downloading it.

Hope this helps.

Read this answer in context 👍 0

All Replies (2)

Wesley Branton
Wesley Branton
more options

Chosen Solution

It sounds like maybe you have accidentally changed the default PDF program that Firefox uses. If you go to the Firefox settings page and scroll down to the Applications section, you should see the Portable Document Format (PDF) content type listed there. You can change the default action to Open in Firefox if you want Firefox to load the PDF instead of downloading it.

Hope this helps.

cor-el
cor-el
  • Top 10 Contributor
  • Moderator
more options

See also: