If a command, menu or button in a toolbar is set with GO PATH=Coll://{any file collection} FOLDERCONTENT, the icons may not be drawn properly if they are shortcuts or .url files. They seem to be drawn, but then have another icon drawn on top.
It will look like this:
In addition it'll be much slower to fetch the icons, and may stop responding. Direct executables without a shortcut are rendered fine.
I realise that using a collection, FOLDERCONTENT, and shortcuts all at the same time is a bit unusual, but I can confirm this did work in DOpus 12, but not in 13. Also, adding the same shortcut and .url icons manually (i.e. dragging them into the toolbar) still works as expected.
To reproduce on current DOpus 13, create a file collection, call it Test. Add a handful of icons to it, making sure some are shortcuts or .urls with icons (such as Steam games). Create a toolbar. Add a new button, edit it, uncheck show label, make sure show image is checked. Edit the command so it says
GO Coll://Test FOLDERCONTENT
Now click Ok and Ok again for the toolbar to be added. You should see the weird icons. They are shown correctly on DOpus 12.