Creating new page via URL does not respect protocol in AJAX request

Environment:

Apache Reverse Proxy in Front of Tomcat 7

where

browser (https) =>  [ Proxy (https) => Proxy (http) ] => Tomcat (http)

When creating a new document based on a template via an crafted url:

https://server/test/xwiki/bin/inline/Internal/Applications/CRM/DATA/App-CRM-CompanyDATA/WPHV6pihzCDCeItx?template=Internal.Applications.CRM.Classes.App-CRM-CompanyClass.App-CRM-CompanyTemplate&parent=xwiki%3ANInternal.Applications.CRM.DATA.App-CRM-CompanyDATA&title=WPHV6pihzCDCeItx

The request works out, the page is created, but while saving via the Save&View button, there is an error at the bottom of the page to be saved stating that the page could not be saved and xwiki does not navigate away from the edit mode ... But the page is saved successfully.

It turns out, that the issue is related to not honouring the protocol

xwiki.cfg:xwiki.url.protocol=https

for this request:

http://server/test/xwiki/rest/jobstatus/refactoring/create/1586622719386-290?media=json

It should be https. Switching tomcat to https resolved the problem, since tomcat / xwiki sees https as request and creates an https response in return ...