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