After I calmed down and tried a search without my swear words, I found three promising work arounds.
Solution 1: Change Your Firefox Configuration
The first solution came from Dave Austin who posted a video tutorial showing how to change one of Firefox’s configuration settings called:
dom.disable_window_open_feature.resizable.
To adjust this setting,
1. Open Firefox
2. Type about:config in the address bar
3. Scroll down the list till you find the entry. (See highlighted item in picture below.)
4. If the entry reads “false”, double-click the line. The value should change to true.
5. Close your browser
If you want to find more information about this configuration item, you can read the Mozilla.Org’s Firefox Tips & Tricks page.
Solution 2: Use the Web Developer Toolbar
This is a good example of how when you’re frustrated you don’t think of some of the immediate solutions. In this case, I spotted a fix posted by Jon Gibbons on disappearing Firefox windows.
Jon’s solution is to install the web developer’s toolbar. As you might have guessed, I already had the toolbar installed, but never thought of using it to resize the second window. You can see the toolbar as Item 2 in the screen snap above. Rather than using the button, I right-clicked the popup window and selected Resize from the menu.
Solution 3: Use a Resize Bookmarklet
I didn’t try this solution which was mentioned on Jon’s site. He points to a java script bookmarklet from Nicholas Roussos. The idea is you select one of three sizes for the pop up window and save that code snippet as a bookmark. When you encounter a problem window, click the bookmark.
To use this bookmarklet, you will need to have checked Move or resize existing windows checked in the Enable Javascript section. I know some people prefer not having this item enabled for security reasons.
I suspect these solutions will solve your problem as they did for me. If not, you have my permission to swear.