The following warnings should be fixed:

GridBagLayout.html:
line 481 column 2 - Warning: trimming empty <p>
line 1332 column 2 - Warning: trimming empty <p>
line 1355 column 2 - Warning: trimming empty <p>

doc-files/Modality.html
line 402 column 11 - Warning: <img> lacks "alt" attribute
line 421 column 11 - Warning: <img> lacks "alt" attribute
line 443 column 11 - Warning: <img> lacks "alt" attribute
line 465 column 11 - Warning: <img> lacks "alt" attribute
line 92 column 9 - Warning: trimming empty <p>
line 112 column 5 - Warning: trimming empty <p>
line 159 column 5 - Warning: trimming empty <p>
line 280 column 5 - Warning: trimming empty <p>
line 291 column 5 - Warning: trimming empty <p>