Restore the check-box for attaching screenshots
Make the screenshot capture a default or restore the checkbox so that users can easily add a screen shot. The "Send us a message" widget used to just have a checkbox for users to include a screenshot and since removing that the percentage of screenshots has greatly decreased and we always have to ask customers to include a screenshot and some of the older ones we have had to call and instruct them on how to include a screenshot. It used to be a lot more intuitive. The minor change is an annoying step backwards.
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Fabiola Gorczany commented
Even having the "Attach a screenshot or file" label appear constantly by the camera icon (rather than only on hover) would probably help. (I'd guess it doesn't occur to most users the camera would add a screenshot, and they simply ignore it.)