Apache2 reverse-proxy with LDAP-authentication, HTTPS and URL-path-prefix

Sorry to come back on this topic so late.
However, just tried to implement this apache configuration for the reverse proxy - which is working fine in principle, but I could not bring charts and also linked external websites to work with this config.
Adding a

Substitute "s|'/chart'|'/openhab/chart'|n"

does not help.

For external website embedding I’m using Webview in the sitemap e.g. something like that in the sitemap.

Webview item=myitem label="myLabel" url="http://xxx.yyy.zzz/bin/xx.exe/dn?L=vs_liveticker&evaId=1231801" height=8

For reference, by apache config after the LDAP section (which is working fine by the way)

                RewriteEngine On
		RewriteCond %{HTTPS} !=on 
		RewriteRule "/openhab/openhab/(.*)" "/openhab/$1" [R,L]
		#RewriteRule "/openhab/?(.*)" "http://localhost:10080/$1" [P,L]
		RewriteRule "/openhab/?(.*)" "http://xxx.yyy.zzz:8080/$1" [P,L]

		#RedirectMatch permanent ^/$ /openhab.app?sitemap=default
		#RedirectMatch permanent "^/openhab$" "/start/index"

		## We cannot use ProxyPass, because this implicitly adds its own rewrite-rules *before* ours!
		## Hence, we cannot redirect the browser from .../openhab/openhab/... to .../openhab/...!
		#               ProxyPass http://localhost:10080
		#               ProxyPassReverse http://localhost:10080
		ProxyPassReverse http://xxx.yyy.zzz:8080/
		
		ProxyHTMLEnable On

		## The ProxyHTMLExtended can be used to work on *embedded* JavaScript. It does not work
		## on separate .js-files. Thus, I now use SUBSTITUTE instead -- which works on both separate
		## and embedded. Thus, this ProxyHTML* is not needed, anymore.
		#               ProxyHTMLExtended On
		#               ProxyHTMLURLMap / /openhab/ [e]
		#               ProxyHTMLURLMap /basicui /openhab/basicui
		#               ProxyHTMLURLMap /openhab/basicui /openhab/basicui

		## Seems the suppression of gzip is not needed. Found this hint in the web,
		## before, but the problem was actually another one. Thus, commented the following line
		## again.
		## UPDATE: IT IS NEEDED! My smarthome.js was obviously cached, before.
		RequestHeader unset Accept-Encoding

		AddOutputFilterByType SUBSTITUTE text/html
		AddOutputFilterByType SUBSTITUTE text/css
		AddOutputFilterByType SUBSTITUTE application/javascript
		AddOutputFilterByType SUBSTITUTE application/json
		Substitute "s|/basicui/|/openhab/basicui/|n"
		Substitute "s|/rest/|/openhab/rest/|n"
		Substitute "s|'/rest'|'/openhab/rest'|n"
		Substitute "s|/paperui/|/openhab/paperui/|n"
		Substitute "s|/inbox/|/openhab/inbox/|n"
		Substitute "s|/icon/|/openhab/icon/|n"
		Substitute "s|http://|https://|n"
		
		Substitute "s|/habpanel/|/openhab/habpanel/|n"
		Substitute "s|/habmin/|/openhab/habmin/|n"
		
		Substitute "s|'/chart'|'/openhab/chart'|n"
		Substitute "s|'/start'|'/openhab/start'|n"

Does charts or external webview elements in sitemap display correctly on your side with the provided config?
If not what to add for charts and external websites to work correctrly behind the apache reverse proxy?

Thanks for any hint.