Reset the page zoom on pages that cause problems, make sure that the window is not maximized:

• View > Zoom > Reset (Ctrl+0 (zero); Cmd+0 on Mac)
• http://kb.mozillazine.org/Zoom_text_of_web_pages

Well that tip didn't help at all. The problem still persists. In the past this situation has cropped up on other web pages too.

If you have increased the minimum font size then try the default setting "none" as a high value can cause.

• Firefox > Preferences > Content : Fonts & Colors > Advanced > Minimum Font Size (none)

Make sure that you allow websites to choose their fonts.

• Firefox > Preferences > Content : Fonts & Colors > Advanced > [X] "Allow pages to choose their own fonts, instead of my selections above"

You can use an extension to set a default font size and page zoom on web pages.

• Default FullZoom Level: https://addons.mozilla.org/firefox/addon/default-fullzoom-level/
• NoSquint: https://addons.mozilla.org/firefox/addon/nosquint/

Nope that don't help. The content still runs off the bottom of the page and the scroll bar doesn't go all the down to view all the content.

If that are Flash objects then try to open the right-click context menu on that object to see if the object is zoomed.

Hi again, no it is not a flash object. I inspected it with firebug and it was all tagged with "div" tags. no flash.

here is the link:

https://apps.facebook.com/chasecommunitygiving/ I click on: "Leaderboard>>Top 100" and that page with a simple listing runs off the bottom of the firefox window with not adequate scrolling to view all the presented content.

Can you attach a screenshot?

• http://en.wikipedia.org/wiki/Screenshot

Use a compressed image type like PNG or JPG to save the screenshot and make sure that you do not exceed the maximum file size (1 MB).

here it is.

That content is in a not scrollable iframe.
The height of that frame is probably set via JavaScript to the correct height after that iframe has loaded and that didn't seem to have happened in your case and you only get the default height of about 600px.
You can try to right click in that frame: This Frame > Open Frame in New Tab

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Firefox > Preferences > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox > Preferences > Privacy > Cookies: "Show Cookies"

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.
• https://support.mozilla.com/kb/Safe+Mode