The dropdown opens and a js exception is thrown:
"Ignored attempt to cancel a touchend event with cancelable=false, for example because scrolling is in progress and cannot be interrupted."
The dropdown does not open (similarly to the way the DropDownList behaves in the same scenario).
Hello ladies and gentlemen.
Readonly mode does not work correctly in Bootstrap 4 Theme.
If the MultiSelect is put into readonly mode programmatically and has a value and clearButton option is true - clear button is displayed and the value can be cleared.