ef="http://www.opengl.org/registry/specs/EXT/visual_rating.txt">EXT_visual_rating</a></td></tr>
<tr><td><br></td><td></td><td></td></tr>
<tr><td class="num">18</td><td>&nbsp;</td><td><a href="http://www.opengl.org/registry/specs/INTEL/swap_event.txt">INTEL_swap_event</a></td></tr>
<tr><td><br></td><td></td><td></td></tr>
<tr><td class="num">19</td><td>&nbsp;</td><td><a href="http://www.opengl.org/registry/specs/MESA/agp_offset.txt">MESA_agp_offset</a></td></tr>
<tr><td class="num">20</td><td>&nbsp;</td