You are missing type = "button".
In the original boot source, fewer files exist, there are several CSS rules defined for the input rule [type = "button"]. ( Checked for version 3.3.6 )
You may not have to use it, but it is intended to be used with type = "button".
Both W3School and Bootstrap button demos use type = "button"
Your code:
<button class="btn btn-primary">Hello</button>
W3:
<button type="button" class="btn btn-default">Default</button>
If it doesnβt work after adding type = "button" (either submit or reset), try looking at your element with the inspector and see what overrides the css pointer rule: cursor.
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