This is a testharness.js-based test.
[FAIL] Inserting "XY" after deleting last character in a non-collapsed range of a link in <b> and containing <i> (Direct typing) in <p><b><a href="about:blank"><i>abc[d]</i></a></b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>abcX</i></a>Y</b></p>" not in array ["<p><b><a href=\\"about:blank\\"><i>abcXY</i></a></b></p>", "<p><b><a href=\\"about:blank\\"><i>abcXY</i></a></b><br></p>"]
[FAIL] Inserting "XY" after deleting text after middle of a link in <b> and containing <i> (Direct typing) in <p><b><a href="about:blank"><i>ab[cd</i></a>de]f</b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>ab</i></a><i>XY</i>f</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b></p>", "<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b><br></p>"]
[FAIL] Inserting "XY" after deleting first character of a link in <b> and containing <i> (Backspace) in <p><b><a href="about:blank"><i>[z]abc</i></a></b></p>
assert_in_array: value "<p><b>XY<a href=\\"about:blank\\"><i>abc</i></a></b></p>" not in array ["<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b></p>", "<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b><br></p>"]
[FAIL] Inserting "XY" after deleting last character in a non-collapsed range of a link in <b> and containing <i> (Backspace) in <p><b><a href="about:blank"><i>abc[d]</i></a></b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>abc</i></a>XY</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b></p>", "<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b><br></p>"]
[FAIL] Inserting "XY" after deleting text after middle of a link in <b> and containing <i> (Backspace) in <p><b><a href="about:blank"><i>ab[cd</i></a>de]f</b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>ab</i></a><i>XY</i>f</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b></p>", "<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b><br></p>"]
[FAIL] Inserting "XY" after deleting first character of a link in <b> and containing <i> (Delete) in <p><b><a href="about:blank"><i>[z]abc</i></a></b></p>
assert_in_array: value "<p><b>XY<a href=\\"about:blank\\"><i>abc</i></a></b></p>" not in array ["<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b></p>", "<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b><br></p>"]
[FAIL] Inserting "XY" after deleting last character in a non-collapsed range of a link in <b> and containing <i> (Delete) in <p><b><a href="about:blank"><i>abc[d]</i></a></b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>abc</i></a>XY</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b></p>", "<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b><br></p>"]
[FAIL] Inserting "XY" after deleting text after middle of a link in <b> and containing <i> (Delete) in <p><b><a href="about:blank"><i>ab[cd</i></a>de]f</b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>ab</i></a><i>XY</i>f</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b></p>", "<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b><br></p>"]
[FAIL] Inserting "XY" after deleting first character of a link in <b> and containing <i> (execCommand("delete")) in <p><b><a href="about:blank"><i>[z]abc</i></a></b></p>
assert_in_array: value "<p><b>XY<a href=\\"about:blank\\"><i>abc</i></a></b></p>" not in array ["<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b></p>", "<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b><br></p>"]
[FAIL] Inserting "XY" after deleting last character in a non-collapsed range of a link in <b> and containing <i> (execCommand("delete")) in <p><b><a href="about:blank"><i>abc[d]</i></a></b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>abc</i></a>XY</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b></p>", "<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b><br></p>"]
[FAIL] Inserting "XY" after deleting text after middle of a link in <b> and containing <i> (execCommand("delete")) in <p><b><a href="about:blank"><i>ab[cd</i></a>de]f</b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>ab</i></a><i>XY</i>f</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b></p>", "<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b><br></p>"]
[FAIL] Inserting "XY" after deleting first character of a link in <b> and containing <i> (execCommand("forwarddelete")) in <p><b><a href="about:blank"><i>[z]abc</i></a></b></p>
assert_in_array: value "<p><b>XY<a href=\\"about:blank\\"><i>abc</i></a></b></p>" not in array ["<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b></p>", "<p><b><i>XY<a href=\\"about:blank\\">abc</a></i></b><br></p>"]
[FAIL] Inserting "XY" after deleting last character in a non-collapsed range of a link in <b> and containing <i> (execCommand("forwarddelete")) in <p><b><a href="about:blank"><i>abc[d]</i></a></b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>abc</i></a>XY</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b></p>", "<p><b><i><a href=\\"about:blank\\">abc</a>XY</i></b><br></p>"]
[FAIL] Inserting "XY" after deleting text after middle of a link in <b> and containing <i> (execCommand("forwarddelete")) in <p><b><a href="about:blank"><i>ab[cd</i></a>de]f</b></p>
assert_in_array: value "<p><b><a href=\\"about:blank\\"><i>ab</i></a><i>XY</i>f</b></p>" not in array ["<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b></p>", "<p><b><i><a href=\\"about:blank\\">ab</a>XY</i>f</b><br></p>"]
Harness: the test ran to completion.