Have you tried 192.168.4.100:8080/recipes/default/tiddlers.json
? Can you access it? Also try 192.168.4.100:8080/recipes/default/tiddlers.json?filter=[tags[]]
. This is the easiest way to know if your server is providing API.
I think extension it self is working, you can try use it with TidGi Desktop https://tidgi.fun/ , if you are not a technical person. Or you can start a new post in the forum about this issue, because I think it is not relevant to clipper extension now.