First method – If you have list of sites
1.Open Firefox.
2.Click tools and then select options…

3.Click content tab in options window
4.And then click 2nd Exceptions… button
5.Type website address
6.Click on block button

7.Click close , and then close option window
8.Close Firefox , and start again
Second method – currently open site
1.Open Firefox.
2.Click tools and then select Page Info

3.Click Media tab in page info window
4.Select Block images form check box

5.And close page info window
6.Close Firefox , and start again
Note:
1.After this configuration, generally images all block, but if display image, remove your cache and restart Firefox again.
2.If image domain name (site address) and block site domain name (site address) are different, Firefox doesn’t block images.


The blocking image is working fine in FF – Too Good, now I want to unblock. How to do that?
The blocked image its now not displaying in the Media tab, even I reinstalled the FF.
deen , follow 1-4 steps , select site and then click remove site and close
ashish choudhary, now I got it and many Thanks