First of all, thanks for the amazing editor!
I know this is not the section for plugin errors, but I believe that the plugin itself is working fine, because I encountered this for the first time only recently, and I definitely remember my Paint.NET updating a week ago or so...
The recent update broken the ico/cur plugin, it seems. On opening an ico file, the entire app freezes due to the modal window, that asks the user to pick which icon to open, not showing on top of the Paint.Net window. Some alt-tabbing back and forth helps bringing said modal window back from the abyss...
I've been using the ico/cur plugin for years, and the modal window that is used to pick the resolution or open everything in different layers never presented any problems to me until now.
In case it helps, I'm using win7pro 64-bit, with a classic theme.
I've uploaded a video showing the weird behavior.
I should also make clear that this bug is of very strange, fleeting nature. After a few tries with a single instance of Paint.NET, the weird behavior usually disappears, and the modal window shows as it should, but once I restart Paint.NET, I'm getting the freezes (i.e. modal dialogs behind the main window) again.
I do not want to spam and duplicate this topic into the plugins forum branch, but if it belongs there more than here, please move it.