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I'm having to design inside an iframe for an upcoming Blinksale feature (ugh, i know), and I wanted to keep the iframe at a fixed height so that scrollbars would never appear (thus ruining the happy illusion that the iframe UI is integrated into Blinksale).

So, when we have to display an error message for a form element, we replace the default label with an error-specific label. Keeps the form from increasing in height and forcing a scrollbar in the iframe.