Hm, I will have a closer look asap, but in the meantime, can you see the jsoup?
Should be in karaf like:
openhab> bundle:list
yyy Active 80 1.14.3 jsoup Java HTML Parser
unfortunately not…
openhab> bundle:list | grep jsoup
openhab>
both JARs are still deployed in addons folder
-rw-r--r-- 1 openhab openhab 4358 Jan 21 14:14 jsoup-1.14.3.jar
-rw-r--r-- 1 openhab openhab 79692 Jan 13 15:08 org.openhab.binding.broadlink-3.4.3-SNAPSHOT.jar
I can see differences regarded to size,
mine jsoup is like 423395 and mine kostal is like 93687
Please see below,
ls -l
-rw-rw-r-- 1 basse basse 423395 dec 20 2021 jsoup-1.14.3.jar
-rw-r–r-- 1 basse basse 93687 dec 4 17:35 org.openhab.binding.kostalinverter-4.0.0-SNAPSHOT.jar
oops, I’m sorry! seems like I used the wrong links from github… when using raw link I have the same size:
-rw-rw-r-- 1 oliver oliver 423395 Jan 22 17:17 jsoup-1.14.3.jar
-rw-rw-r-- 1 oliver oliver 93687 Jan 22 17:13 org.openhab.binding.kostalinverter-4.0.0-SNAPSHOT.jar
Now the binding is getting deployed (still with some error messages) and showing active in karaf:
openhab> bundle:list | grep Kos
325 x Active x 80 x 4.0.0.202312041635 x openHAB Add-ons :: Bundles :: Kostal Binding
And finally my kostal thing is online with all channels 
2024-01-22 17:16:03.121 [WARN ] [org.apache.felix.fileinstall ] - Error while starting bundle: file:/usr/share/openhab/addons/org.openhab.binding.kostalinverter-4.0.0-SNAPSHOT.jar
org.osgi.framework.BundleException: Could not resolve module: org.openhab.binding.kostalinverter [323]
Unresolved requirement: Import-Package: org.jsoup; version="[1.14.0,2.0.0)"
at org.eclipse.osgi.container.Module.start(Module.java:463) ~[org.eclipse.osgi-3.18.0.jar:?]
at org.eclipse.osgi.internal.framework.EquinoxBundle.start(EquinoxBundle.java:445) ~[org.eclipse.osgi-3.18.0.jar:?]
at org.apache.felix.fileinstall.internal.DirectoryWatcher.startBundle(DirectoryWatcher.java:1260) [bundleFile:3.7.4]
at org.apache.felix.fileinstall.internal.DirectoryWatcher.startBundles(DirectoryWatcher.java:1233) [bundleFile:3.7.4]
at org.apache.felix.fileinstall.internal.DirectoryWatcher.doProcess(DirectoryWatcher.java:520) [bundleFile:3.7.4]
at org.apache.felix.fileinstall.internal.DirectoryWatcher.process(DirectoryWatcher.java:365) [bundleFile:3.7.4]
at org.apache.felix.fileinstall.internal.DirectoryWatcher.run(DirectoryWatcher.java:316) [bundleFile:3.7.4]
2024-01-22 17:25:07.545 [INFO ] [el.core.internal.ModelRepositoryImpl] - Loading model 'kostal.things'
I will now test the channels and let you know my results.
Thanks a lot for you quick support!