today, prior to releasing a new version of the dub plugin I added an svg icon to src/main/resources/META-INF/pluginIcon.svg as per the documentation.
As my image should be fine for the default theme or darcula, I didn't bother with a pluginIcon_dark.svg version.
If I call the API url for the default theme the icon works
but with Darcula I get a 404
That seems fair as I didn't put a pluginIcon_dark.svg image into META-INF but it would be a lot better if the API would return the pluginIcon.svg if a pluginIcon_dark.svg has not been set. In my case the dark version would be identical as there's no need for it to look different to the standard one.