Returns true or false depending on how event was initialized. True if
event goes through its target's ancestors in reverse tree order, and
false otherwise.
Returns true or false depending on how event was initialized. Its return
value does not always carry meaning, but true can indicate that part of the
operation during which event was dispatched, can be canceled by invoking
the preventDefault() method.
Returns true or false depending on how event was initialized. True if
event invokes listeners past a ShadowRoot node that is the root of its
target, and false otherwise.