Paste a shortcode into a Custom HTML widget and WordPress prints it exactly as you typed it — [contact-form], square brackets and all — instead of running it. This plugin fixes that, and nothing else.
When this plugin was written in 2011, WordPress ran no shortcodes in any widget, and one line of code fixed it for every sidebar on the site. WordPress has caught up since:
So the plugin now does the one thing that is still missing. Where core already handles shortcodes, it deliberately stays out of the way — running them a second time is not a feature.
If you have been using version 3.0 on a recent WordPress, this release is also a bug fix. The old code hooked shortcodes onto the Text widget in a way that made core skip its own, correctly ordered pass, and shortcode output could come out with paragraph tags injected into the middle of it. That no longer happens.
The plugin collects nothing, stores nothing, and makes no external requests.