Server: Updates clears 'theme' entry in config.php

[greyman-hh]

Every time I update Nextcloud the theme entry in the config.php get cleared.

I use
'theme' => $_SERVER['HTTP_HOST'],

after an update the entry is

'theme' => '',

[nextcloud-bot]

GitMate.io thinks possibly related issues are https://github.com/nextcloud/server/issues/11038 (Updating App will enable maintenance in config.php ...), https://github.com/nextcloud/server/pull/11240 (Consider openssl settings from config.php), https://github.com/nextcloud/server/pull/11047 (Fix typo in config.sample.php), https://github.com/nextcloud/server/issues/1358 (config.php - Disable Remember Login), and https://github.com/nextcloud/server/pull/10744 (Update help.php).

[ChristophWurst]

I don't think you're "allowed" to use vars in config.php because that file is re-written by Nextcloud when system config changes. cc @MorrisJobke

[kesselb]

You could create a new file theme.config.php in the same folder like config.php and use

return [
    'theme' => $_SERVER['HTTP_HOST']
];

this should be update save.

[MorrisJobke]

With the solution of @danielkesselberg the theme is always also fetched from this additional file and will not be vanished on update.