Sorry for open another issue for a already closed subject, but I'm not pretty sure if it's a expected behavior.

At the newest bootstrap library, we can find this rule:

"
.btn.disabled, .btn[disabled], fieldset[disabled] .btn {
pointer-events: none;
cursor: not-allowed;
filter: alpha(opacity=65);
-webkit-box-shadow: none;
box-shadow: none;
opacity: .65;
}
"

So I assume that bootstrap tried to implement the cursor: not-allowed for disabled buttons, or input's.

I have created two jsfiddles. The only diference between both, is that one has the bootstrap-min.css imported and the other don't.

We can see that when I don't import the bootstrap library, everything works fine and when I import, it doesn't work anymore.

jsfiddle with bootstrap imported: https://jsfiddle.net/3sq410wk/
jsfiddle without bootstap css: https://jsfiddle.net/f2t9ahqe/