I use LaunchBar and it sometimes loses the custom icon. I have asked the vendor for support and will answer should I get an answer, but I wondered if I could find a cause or fix for missing icon previews on the OS level.
What's super odd is that Finder and the macOS app switcher show the correct icons - just LaunchBar 6 Version 6.9.4 seems to be dropping the icons. I'm seeing this on 10.12.6 and 10.13.x and the issue persists after a reboot.
Is there an icon services API or subsystem that could need rebuilding or is this just a third party issue where the tool needs a fix or reset?