Thanks for the help so far and understand such issues can be difficult to test and debug.
I’ve just now checked it myself a third computer and the issue was replicated after clicking through around 5 articles. I’ve attached what I think is the log you requested. Apologies if it isn’t what you wanted.
Two of the computers have resolution 1680*1050 on Windows 7 Home Premium. While, the other on the same operating system with a resolution of 1366*768. As part of the testing process we disabled all Firefox plugins.
Hope that helps,