Having said that my HTML is generated with CGI.pm in a CGI::Application framework.

You could of course post the piece of code that generates the tables. You could narrow it down to the essential bits, and then post it. I'm quite sure that would be a lot less than 18 kB. Not only would that have made it possible for us to find the bug and help you, it would also have made your post on-topic. Besides, 18 kB is reasonable for publishing on your scratch pad.

Is there any widely known differences between the two versions of Mozilla that I may be unaware of?

Apart from built-in true type font support? Not that I know of.

Are there any pitfalls I should avoid when generating HTML for Mozilla 0.9.9 ?

You could do a search query on bugzilla to find out. That's the home of all (and there are many!) bugs that are reported for Mozilla.

I figured there would be some monks here using a similar combination of applications as I am, and thought this may not be unreasonable.

I use Mozilla and have recently upgraded to 0.9.9. At first, I encountered a bug regarding forms, but it was not reproducable. I'd be happy to help, but that requires that you give the information needed. We cannot guess the structure of your table, we cannot guess the nature of the bug (does Mozilla segfault? does it display a message?)

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