This is a testharness.js-based test.
[FAIL] Backspace at "<p>ab[c<span contenteditable="false">no]n-editable</span>def</p>"
  assert_equals: If only editable text is deleted, its target range should be the deleted text range expected "(#text \\"ab\\", 2) - (#text \\"ab\\", 3)" but got "(#text \\"ab\\", 2) - (<span>, 0)"
[FAIL] Backspace at "<p contenteditable="false"><span contenteditable>a[bc</span>non-editable<span contenteditable>de]f</span></p>"
  assert_equals: If editable text before non-editable element is deleted, its input type should be deleteContent expected "deleteContent" but got "deleteContentBackward"
[FAIL] Backspace at "<p>a[bc<span contenteditable="false">non-editable<span contenteditable>de]f</span></span></p>"
  assert_equals: If editable text before non-editable element is deleted, its target range should be only the deleted text expected "(#text \\"a\\", 1) - (#text \\"a\\", 3)" but got "(#text \\"a\\", 1) - (<span>, 0)"
Harness: the test ran to completion.