hm it doesn't seem to pick up the wp installation if the WP_CONTENT_DIR is changed. should be an easy fix, se below.
this site is very much wordpress: https://www.berghs.se/ but wpdetective won't detect wordpress at all. it has a custom WP_CONTENT_DIR.
here's a similar but less polished version my team created some years ago: http://wppluginchecker.earthpeople.se/?wordpress-site=https%...
it tries a few common variables for WP_CONTENT_DIR, and runs completely in the browser, should you want to take a peek on how we detect WP.