I have a release that doesn’t have cover art from the archive and it is not detected in Picard, although it has cover art from Amazon.
For Amazon there is a plug-in. You need to download and enable the plugin in Options > Plugins. Afterwards you can enable it as a cover art providers in Options > Cover Art.
Thanks! I’ve taken a look at least three times at the settings, but still somehow managed to miss that there are plugins to this awesome program.
The Plugins are one of the great features The cover art Plugins are a bit awkward to activate, as you have to save the options first after activating it, then go back to Options > Cover Art to enable the new cover art providers. This is a known issue we still need to improve, but luckily one doesn’t do this often.
For completeness and for others stumbling across this thread: We have an entire section in the documentation on why cover art might not show up and what to do about it. There is also documentation on the different cover art providers, including the current plugins.