Summary:

In Iceweasel (it's effectively Firefox), I want to block all images, but allow
images on websites I specify. But the standard method to do this is not working.

The way you're supposed to be able to do this is as follows. In Iceweasel,
select Edit/Preferences/Content and UNCHECK LoadImagesAutomatically. Select
Exceptions, enter a website name, select "Allow". Now, Iceweasel should display
images for websites with the "Allow" designaton, but not for any other site.

But images are NOT displayed on the "Allowed" sites. NO images are shown on any
sites. And I've got the NoScript extension disabled. I have no other extensions.

Am I doing something wrong? If I have to use a workround, I don't want an
extension that just toggles images on and off. I want to have images blocked by
default, and only allow them on sites I choose. Many thanks if you have a
solution.

Full Details:

I'm using Iceweasel 10.0.4. Is this an Iceweasel bug? Is there a workround?

CHECKING LoadImagesAutomatically does display images on all sites as you'd
expect.

10.0.4??? That's ancient. The current version is 31. Upgrading to a more current version might help.

Yeah, very old version

Also note that images may be hosted on server that differs from the 'main site'

www.example.com
images.thirdparty.com/example.com/....