Issue with main stylesheet/canonical link and WP in subdir?

AFAIK the stylesheet and canonical links are supposed to form a fully featured stylesheet link, right?

Now I developed locally on a local URL resembling,

Then uploaded the files to the client’s testserver but: CSS formatting is missing. Checking the page’s source code I found this:

<link rel="stylesheet" href="/tvv_wordpress/wordpress/wp-content/themes/tvv/assets/css/main.min.css?">
<link rel="canonical" href="">

Where and how is the stylesheet link configured? Checking lib/scripts.php I cannot find anything unusual…

OK, figured out that it must be related to the stage switcher plugin and the

define('WP_ENV', 'development');

in wp-config.php

I’ve activated this setting locally but it wasn’t on the “staging” environement (basically it’s a temp installation on the client’s server). So after I updated it, it works…

I’m not using this as my clients mainly use shared hosting which doesn’t provide for SSH access.

So, can somebody briefly explain to me how to do it properly the old fashioned way ?