No problems here with opening this image.

Are there any messages in the Web Console about this image?

• "3-bar" menu button or Tools -> Web Developer
• https://developer.mozilla.org/en/Tools/Web_Console

If images are missing then check that you do not block images from some domains.

• you can tap the Alt key or press the F10 key to show the hidden Menu Bar temporarily

Check the permissions for the domain in the currently selected tab in "Tools -> Page Info -> Permissions".

Check "Tools -> Page Info -> Media" for blocked images

• select the first image and use the cursor Down key to scroll through the list
• if an image in the list is grayed and "Block Images from..." has a checkmark then remove this checkmark to unblock images from this domain

You can check these preferences on the about:config page and make sure they have the default value.

• permissions.default.image (1)
• network.http..sendRefererHeader (2)

There is Tracking Protection that can block (wanted) content, so check the location/address bar for special icons.

• https://support.mozilla.org/en-US/kb/control-center-site-privacy-and-security-firefox

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block (wanted) content (e.g. Adblock Plus, NoScript, Ghostery, uBlock Origin) always make sure such extensions do not block (wanted) content.

• make sure your extensions and filters are updated to the latest version

See also:

• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems
• http://kb.mozillazine.org/Images_or_animations_do_not_load
• http://kb.mozillazine.org/Websites_look_wrong

Web Console: GET http://www.mattlibrary.org/images/0014(1).jpg [HTTP/1.1 200 OK 746ms] SyntaxError: applying the 'delete' operator to an unqualified name is deprecated eval:3:27

"Tools -> Page Info -> Media": image is not blocked

   permissions.default.image (1)
   network.http.sendRefererHeader (2) 

are set as expected

tracking protection does not detect tracking elements

I have uBlock/noscript but disabling them doesn't fix the problem

when I click "edit and resend" the type =image is recognized:

patrickdrd said

when I click "edit and resend" the type =image is recognized:

The tiny thumbnail image in the Network Monitor is promising. I think that means the image was successfully retrieved.

What did you edit, or did you just resend?

And then did the image display in the tab as expected?

I just resent it, no edit, but the image still wasn't displayed in the tab

This only affects "stand alone" images (URL directly to the image) and not images displayed in web pages?

Do you use any other extensions or custom style rules that might affect content? As a rough test, you could test in Firefox's Safe Mode. In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any difference? (More info: Diagnose Firefox issues using Troubleshoot Mode)

It is possible that security software (anti-virus, firewall) is causing the problem. Try to disable security software temporarily to see whether that makes a difference.

jscher2000 said

This only affects "stand alone" images (URL directly to the image) and not images displayed in web pages? Do you use any other extensions or custom style rules that might affect content? As a rough test, you could test in Firefox's Safe Mode. In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem. If Firefox is not running: Hold down the Shift key when starting Firefox. If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart. Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh). Any difference? (More info: Diagnose Firefox issues using Troubleshoot Mode)

yes, only stand-alone images were affected, I restarted in safe-mode and images were displayed, so I disabled all add-ons and started enabling one by one, it only worked when greasemonkey was disabled, so I checked my user scripts and some ad-blocking scipts (an ad-blocker detector killer and adsbypasser) were the culprits, the only was I got to see the images was disabling both of them, disabling one only wasn't enough!

thanks for the answers, help and support guys!