Since 11.17.2 beta, the icons for .mkv files on my networked drive are just displaying a blank icon. When viewed in explorer they are showing the correct icon. As soon as a file is moved to a drive on my PC the icon shows correctly in dopus.
Check that Preferences / Folders / Folder Display / Show generic icons for: Network Drives is not on.
Thanks very much, that sorted it out. I have no idea how that setting got changed though.