Ok @tose , it WORKS now and I need to test it, but before I do, I want to help you.
Here are some clarifications that you should be providing in your articles:
It is not obvious what the user needs to do, there are many options on the page you link to, including big green buttons that download the wrong files. Instead, the user must go here https://cdn.jsdelivr.net/npm/vue/dist/ and download the vue.js file.
2. vue resource
Again, it is not obvious as different branches are selected on the landing page depending on the user GitHub settings - if indeed they have an account? The user must click on branch and select master because default is the latest which does not work.
Then the user must download and unpack the project and must then rename the directory to vue-resource because by default the downloaded and unzipped directory will be named as: vue-resource-devel or vue-resource-2.0 - if this isnt renamed it will not work !!
In openhab-conf/html/timeline-picker/index.html there is an include for js/vue-resource.js however that file does not exist because when unzipped it creates a directory *vue-resource/… so the user needs to:
cp js/vue-resource/dist/vue-resource.js js/
3. OpenHAB app
The widget in the sitemap does not work with the OpenHAB app, when outside a grouping, but is fine if used in a browser.
4. Rules error
My VScode LSP is generating errors, such as regarding the rules - which I do not understand because I do not code in Java, HTML, CSS or JS.
"message": "Cannot refer to the non-final variable currDay inside a lambda expression",
+ several other similar errors at different src code lines.
None of the icons appear - I just get the usual block square image placeholder for the icon(s).
Apologies if the above is obvious to you, but I assure you it wasnt obvious to me and whilst I am useless at web apps, html, css and JS, I have been using linux for 35+ years ! As you can see, it is not as simple as following your guide - doing that verbatim will not work without the above changes.
Now that you have shown me what can be done by “a few scripts” and style files, I might learn HTML, JS, CSS, JAVA [cough cough] and so on LoL. I would like the background to be black not grey, as my sitemap and browser rendering is on black background. ah well
WELL DONE !!