This refers to my personal experience and installation of Webtrees.
The good people at One.com have some odd ideas about disrupting best practices - and following their own obscure rules.
One of these is to let SSL / HTTPS use port 80 for communication - same as unencryptet HTTP. This breaks any application that - by default - whould use port 443 for HTTPS
HTTPS URLs begin with "https://" and use port 443 by default,
Wikipedia
My hack for SSL / HTTPS on One.com is pretty simple - once you know how
- Searching for _UID
- Handling Danish months convertion to GEDCOM