I have a problem which seems to be quite a rare one and I can safely say I know what exactly what is causing it. After some process of elimination I reached the conclusion that, in a website featuring five main pages - for which different information can be revealed/hidden, in three JavaScript-powered states the user can switch between - one of these pages is currently without this functionality simply because the HTML contains user input controls.
Using alert boxes for troubleshooting, I discovered that one of the arguments passed into the event, which occurs either when the relevant dropdown item or one of the ''tabs'' near the bottom is clicked, is in fact an ''undefined'' value. The purpose of the value is to reset one lot of elements, while two others in the same handlers that are involved in a similar action are always successfully recognised. Essentially all three states are to be made invisible before the next stage of the function, which is to determine what should now appear on screen and carrying it out. Efforts to adjust the way that the string in question is conceived have proven ineffective. This happens regardless of which set of content is being moved to or from, within this particular page.
I was unaware this could even happen. CSS has been ruled out as the culprit; there is no change when all references in the code are removed. Replacing the entire element (including the form tags as opposed to simply leaving the content within it as is) is the only way to replicate the desired results here. My issue has been observed mainly in Chrome; both it and IE9/10 have previously run the scripts without a hitch although the latter is now giving the same result on all five.
Any assistance would be greatly appreciated. Many thanks in advance.