Wappler Version : last stable
Operating System : Mac
Server Model: NodeJS
Database Type: PostgreSQL
Hosting Type: Custom
Now that the spinner is built right into the button properties, a problem has appeared - it duplicates the ID of the button itself, and if you try to change it, Wappler still sets two identical IDs
The problem arises because you have applied the spinner class to the button itself.
The code should read like:
<button id="btn1" class="btn btn-danger">
<span class="spinner-border spinner-border-sm" role="status"></span> Button</button>
Well, yes, but Wappler does it - previously you could separately add the Spinner element from the interface and everything worked fine
One more is a bug too - Wappler does not change the spinner ID in the code when you change it in the interface
Ben, you are both right and wrong at the same time. When Wappler adds a spinner, it doesn't assign an ID to it and there is no error. But if you change the ID of a button, then a duplicate of this ID is assigned to the spinner and it is impossible to change it in the interface. The only way is to change it directly in the code. i.e. a bug - but one that can be bypassed 
Vladimir, I now see the problem.
In my Windows version of Wappler, I do not see:
When I right-click on the button in App Connect, I get:
By using this method, I do not get any errors, even when renaming the button.
I think that @George should have a look at this,
