Someone asked me last week to stop users typing backticks into a product-name field. Fine. Then someone asked for the same thing on a host-address field, then a description field. Three tickets, same shape, three weeks apart. That's the moment a form-validation ask stops being a bug fix and starts being a design question: do I bolt a fourth one-off regex onto a fourth page, or do I finally admit this is a pattern and give it a name? We'd already answered that question once, for a different re...