5709a7858d5c197721be66d5218a79124abadb70
lrnassar
  Tue Mar 17 08:46:31 2026 -0700
Adding alt text to images across static documentation pages, CGI headers, markdown docs, and Pandoc templates. Content images receive AI-generated descriptive alt text; decorative images (icons, spacers, toggles) receive alt="" per WCAG best practice. Also adds Image Descriptions section to the accessibility page, and fixes Pandoc Lua writers to output alt attributes. 67 files, covering help docs, news archive, ENCODE pages, portal pages, and session examples. refs #37254

diff --git src/hg/htdocs/goldenPath/help/hgConvert.html src/hg/htdocs/goldenPath/help/hgConvert.html
index 615e6406283..58d24052dcf 100755
--- src/hg/htdocs/goldenPath/help/hgConvert.html
+++ src/hg/htdocs/goldenPath/help/hgConvert.html
@@ -50,68 +50,68 @@
             <li>Use the <b>Assembly</b> dropdown to select from other assemblies
                 of the same organism (e.g., other human assemblies when the source assembly is
                 hg38). To convert to a different organism, use the Search bar
                 instead.</li>
         </ul>
     </li>
     <li>Check the <b>QuickLift tracks</b> checkbox to carry over your visible tracks,
         custom tracks, and track hubs to the target assembly. Without this checkbox, only the
         coordinate position is converted.
         <ul>
             <li>When a single track from a container track, such as a superTrack or
                 composite, is lifted, the entire container track is carried over to the
                 target genome assembly.</li>
         </ul>
         <div class="text-center">
-        <img src="../../images/QuickLift/quickLiftTracks.png" width='50%'>
+        <img alt="Browser view showing QuickLift converted tracks from a different assembly" src="../../images/QuickLift/quickLiftTracks.png" width='50%'>
         </div>
     </li>
     <li>Click <b>Submit</b>. The results page will show the corresponding position(s)
         in the target assembly with links to the Genome Browser. If
         <font color="#008000">QuickLift</font> was enabled, clicking a link will display your
         lifted tracks under a green
         &quot;<font color="#008000">QuickLift</font> from ...&quot; group in the target
         assembly. To remove <font color="#008000">QuickLift</font> tracks, click the
         <button>Disconnect</button> button.</li>
 </ol>
 
 <a name="visualIndicators"></a>
 <h3>Visual Indicators</h3>
 <p>
 <font color="#008000">QuickLift</font> tracks have a green left-side button bar in the Browser
 graphic (instead of the usual gray):
 </p>
 <div class="text-center">
-<img src="../../images/QuickLift/quickLiftGreenbuttons.png" width='7%'>
+<img alt="Green QuickLift buttons used to convert coordinates between assemblies" src="../../images/QuickLift/quickLiftGreenbuttons.png" width='7%'>
 </div>
 <p>
 The Alignment Differences track displays liftOver differences using triangles and lines:
 </p>
               <ul>
 		<li>Insertions: <font color="#407F00">green</font></li>
 		<li>Deletions: <font color="#00007F">blue</font></li>
 		<li>Double-sided insertions: <font color="#7F7F7F">gray</font> (Both the source
 		and target assemblies contain unalignable sequence between two regions of aligned
 		sequence)</li>
 		<li>Mismatches: <font color="#FF0000">red</font></li>
               </ul>
 <p>
 Mousing over a triangle displays the size base-pair (bp) difference and the type of alignment
 difference.
 </p>
 <div class="text-center">
-<img src="../../images/QuickLift/quickLiftTrianglesMouseOver.png" width='70%'>
+<img alt="QuickLift track with triangle markers indicating alignment differences on mouseover" src="../../images/QuickLift/quickLiftTrianglesMouseOver.png" width='70%'>
 </div>
 <p>
 Clicking a triangle provides the source and target assembly genome positions, DNA sequence
 alignment, including the type of alignment difference with the bases within the currently
 visible browser region.</p>
 
 <a name="unsupportedTypes"></a>
 <h3>Unsupported Track Formats</h3>
 <p><font color="#008000">QuickLift</font> does not support the following track formats:</p>
       <ul>
         <li>WIG &mdash; <a href="/goldenPath/help/bigWig.html" target="_blank">bigWig</a>
             is supported; WIG tracks can be converted to bigWig using the
             <a href="https://hgdownload.soe.ucsc.edu/admin/exe/" target="_blank"><code>wigToBigWig</code></a>
             utility</li>
         <li>BAM</li>