same issue here. (docker container+swag (letsencrypt+nginx container) for rProxy)
What iāve noticed is all URLās in the webui are pointing to HTTPS apart from the webdav and the Server address URL given at https://serverFQDN/nextcloud/settings/user/sync-clients which both reference http:// locations. Iām assuming the desktop client is using the Server Address URL as given on that sync-clients page and thats the issue, but how do we fix?
lilā help here please on what needs to be done!
edit: SOLVED for me. turns out i was missing āoverwriteprotocolā => āhttpsā, in config.php. Iām guessing something has changed recently as my previous build notes havent covered this and nore does swags included rproxy nextcloud config.