It looks like since the update a few hours ago, you setup autoload in composer.json to autoload the plugin, but are still declaring "type": "wordpress-muplugin" thus the plugin is installing into /mu-plugins/ and being loaded by WordPress as well as Composer resulting in an error.
I can see how this could be overlooked as Sage 9 doesn't ship with installer-paths set in composer.json like it does Bedrock, but if they are manually set at a theme-level it will result in the error above.
It looks like since the update a few hours ago, you setup
autoload
incomposer.json
to autoload the plugin, but are still declaring"type": "wordpress-muplugin"
thus the plugin is installing into/mu-plugins/
and being loaded by WordPress as well as Composer resulting in an error.I can see how this could be overlooked as Sage 9 doesn't ship with
installer-paths
set incomposer.json
like it does Bedrock, but if they are manually set at a theme-level it will result in the error above.Thanks in advance for a quick fix.