https://bugzilla.mozilla.org/show_bug.cgi?id=1668133
1668133 - Split off the check of InputEvent.getTargetRanges() result after `beforeinput` event...
RESOLVED (masayuki) in Core - DOM: Events. Last updated 2020-10-06.
the check
https://developer.mozilla.org/en-US/docs/Web/API/InputEvent/getTargetRanges
InputEvent: getTargetRanges() method - Web APIs | MDN
The getTargetRanges() method of the InputEvent interface returns an array of StaticRange objects that will be affected by a change to the DOM if the input...
web apisinputeventmethodmdn