For me at least anytime I had objects already discovered and sitting in my inbox regardless of adding or removing the binding the only way I have been able to get rid of them from inbox is to click select in top right corner then put check in the checkboxes for each discovered thing and then click remove in bottom left side.
If you manually remove those from the inbox do you still get conflicts?
also, you may want to check from console openhab:links orphan list and if you have some openhab:orphan purge just to tidy things up a bit.
I have included some Rademacher things by an .things file, but not for shellies. Does this influence the UI config/ Inbox detection of Shellies?
Should not, but am not sure.
I use UI config only and we generally advise not to mix both.
Either stay with config files or use the UI config.
Understood! Unfortunately I did not find another way for the Rademacher roller shutters in Openhab. 
Why is that ? What Binding ?
I had already removed all discovered things, and I had cleaned up the model.
I have removed the Shelly beta binding. And now I have removed each shelly item from the Inbox as described. But after re-installing the Shelly beta binding, the inbox is not appearing. Can I initiate the discovery as I cannot add things manually for that binding?
In the orphan list, I had quite a few entries 
. I cleaned this by using “openhab :links orphan purge”. Now it is empty 
, many thanks for that hint, but I do not see any additional effect. The Inbox is still empty/ not appearing.
It was via the http-binding (Rademacher Homepilot (DuoFern) via http-Binding - Tutorials & Examples / Solutions - openHAB Community)
This can be configured in the UI as well
Ok . It was some time ago, that I managed that. And I was so happy, to get it running . Maybe I have to rediscover and reinvent 
.
Do you have an idea to initiate the automatic discovery for the Shelly-Beta-Binding?
(When I go back to the “normal” Shelly-Binding it is really working automatically .)
Like any other Binding
Goto Things, press the blue plus button, select the Shelly Binding and hit the blue scan button.
Even after the scan, inbox might still be empty, just give it a couple of minutes.
Not in all, but in some bindings (also in the Shelly-Binding) I can find a scan button, but not in the Shelly-Beta-Binding (which should support the BLU devices):
This is odd, it should work…
Ah, needs to be active
You have missed to install the required californium packages. Please read the instructions for Beta/Dev Binding versions.
Thank you very much. It had some challenges to get the californium package installed. The sudo commands have been unknown (terminal on synology docker), and I could not solve it.
But I read a hint with the Tradfri binding. That installed the needed packages 
. (Btw: is it not possible to include the californium packages also in the shelly beta binding in the same way?)
I uninstalled the Tradfri bundle via console, but in openHab it is still shown as installed!?
Nevertheless, the most important good news are now, that I could auto discover the shelly things. 
Now I have some other challenges, but this thread can be seen as solved in my opinion. I might open other threads correspondingly. 
Many, many thanks for your patience and support!!!
You could just download the packages from Markus repository and place them into your addons folder before adding the shelly beta binding.
Many thanks. I tried that out, but it worked only “partially”. I copied follwing files in the addons folder:
Then I installed the Beta-Binding in OpenHab. I checked by listing the bundles:
Unfortunately the binding was again not active and scanning for things was not possible.
But I followed another hint. After removing of the binding and the Californium bundles, I entered “feature:install openhab-transport-coap” in the console and the Californium packages have been installed:
Then I installed the beta binding in OpenHab, and all bundles are active now:
Also scanning is now working:
And it is working pretty well now .