ifpath is not working when the lister-tab is a collection

@ifpath and similar @modifiers are evaluated before any commands run, so it would be testing the source path not the destination one.

Using scripting would be better here, as you can simply tell Opus to run a command on the destination tab:

function OnClick(clickData)
{
	clickData.func.command.deselect = false;
	var cmd = DOpus.Create.Command();
	if (clickData.func.sourcetab.lister.dual)
	{
		var dest = clickData.func.desttab;
		var path = dest.path;
		if (path.Root() && path == "coll://")
		{
			cmd.SetSourceTab(dest);
			cmd.RunCommand("Delete REMOVECOLLECTION");
		}
	}
}