I think this maybe a repost. If not then I apologise or holding this to myself.
It's a bookmarklet to enable you to quickly unhide hidden input
elements. Some web developers think that hiding sensitive text in a
hidden field is safe. This may help to enlighten them.
Show Hidden Inputs
To use right click the link and choose add to favourites or bookmark this link, then when you are on a page where you want to quickly view the hidden fields, click the "Show Hidden Inputs" bookmark.