Stumbled across a funny little problem with SharePoint and Firefox today. Turns out that with some master pages, Firefox has a problem responding to the “enter key” when using the SearchBoxEx control. In these cases, hitting enter just refreshes the page. I only noticed it because a recent client wanted to hide the Search button. So, it turns out that this problem is actually solved in default.master where Microsoft use two unassuming lines of uncommented code:
All you have to do is add these two lines to your custom master page anywhere before the final
tag.
Thanks to SteveNG for the blog post that solved this for me.