Pico CMS themes not loading

Nextcloud does not recognize Pico themes other than the default.

/srv/dev-disk-by-uuid-9be327d9-d8cf-4891-b6c5-c7745ba2aa85/appdata/nextcloud/config/www/nextcloud/apps/cms_pico/appdata_public/themes
/srv/dev-disk-by-uuid-9be327d9-d8cf-4891-b6c5-c7745ba2aa85/appdata/nextcloud/config/www/nextcloud/apps/cms_pico/appdata/themes
/srv/dev-disk-by-uuid-9be327d9-d8cf-4891-b6c5-c7745ba2aa85/appdata/nextcloud/config/www/nextcloud/apps/cms_pico/vendor/picocms/pico/themes
/srv/dev-disk-by-uuid-9be327d9-d8cf-4891-b6c5-c7745ba2aa85/appdata/nextcloud/config/www/nextcloud/themes
/srv/dev-disk-by-uuid-9be327d9-d8cf-4891-b6c5-c7745ba2aa85/appdata/nextcloud/data/appdata_ocmke58vu0cb/cms_pico/themes

Not quite sure which ‘themes’ folder I should be using. The NC admin panel (settings) says to put the theme in the last folder shown above, but the theme does not show-up in the drop-down list.

I also changed the owner of all theme files to ‘appuser’ to match that of my NC install, to no effect.

Using Nextcloud 27.0.1 (under Docker)
Pico 2.1.4

Files in the theme folder are:

dr-sr-sr-x 5 appuser users 4096 Aug  6 08:10 .
drwxr-sr-x 3 appuser users 4096 Aug  5 22:12 ..
drwxr-sr-x 2 appuser users 4096 Aug  5 22:12 css
drwxr-sr-x 2 appuser users 4096 Aug  5 22:12 img
-rw-r--r-- 1 appuser users 5178 Aug  5 22:12 index.twig
drwxr-sr-x 2 appuser users 4096 Aug  5 22:12 js
-rwxr-xr-x 1 appuser users  976 Aug  6 08:10 pico-theme.yml
-rw-r--r-- 1 appuser users 5702 Aug  5 22:12 post.twig

I manually added to pico-theme.yml file as it was missing, but again, no change.

Seems like some work needs to be done in order for the app to be fully compatible with NC versions >25. Maybe this GitHub issue is of any help: Custom Pico theme selection does not list themes after upgrade to NC26 (and hacky workaround) · Issue #237 · nextcloud/cms_pico · GitHub

ok thanks will check this out.