Enable the accessibility audit for chrome://net-internals

chrome/browser/resources/net_internals/events_view.html

 <!-- ================= Events view =================== -->
 
 <!-- Filter Box: This the top bar which contains the search box.  -->
 <div id=events-view-filter-box>
   <table width=100%>
     <tr>
       <td width=1%>
         <span id=events-view-filter-help-hover class=mouse-over-help-hover>(?)</span>
       </td>
-      <td width=98%><input type="search" incremental id=events-view-filter-input></td>
+      <td width=98%><input type="search" incremental id=events-view-filter-input title="Sort and filter"></td>
       <td width=1% id=events-view-filter-count>(1 of 34)</td>
     </tr>
   </table>
 </div>
 <!-- Inline filter help -->
 <div id=events-view-filter-help class=mouse-over-help>
   Sort options:
   <ul>
     <li>sort:id (default)
     <li>sort:desc
     <li>sort:duration
     <li>sort:type
     <li>-sort:&lt;option&gt; Reverses sort order
   </ul>
 
   Additional filters:
   <ul>
     <li>id:#[,#]*
     <li>type:&lt;type&gt;[,&lt;type&gt;]*
     <li>is:active
     <li>is:error
     <li>-&lt;filter&gt; Inverts a filter.
   </ul>
 </div>
 <!-- Events Box: This the panel on the left which lists the sources -->
 <div id=events-view-source-list>
   <table id=events-view-source-list-table cellspacing=0 cellpadding=0 width=100%>
     <thead>
       <tr>
-        <td style='border-left:0'><input type=checkbox id=events-view-select-all></td>
+        <td style='border-left:0'><input type=checkbox id=events-view-select-all title="Select all"></td>
         <td id=events-view-sort-by-id>ID</td>
         <td id=events-view-sort-by-source>Source Type</td>
         <td id=events-view-sort-by-description width=99%>Description</td>
       </tr>
     </thead>
     <!-- Events table body: This is where request rows go into -->
     <tbody id=events-view-source-list-tbody></tbody>
   </table>
 </div>
 <!-- Splitter Box: This is a handle to resize the vertical divider -->
 <div id=events-view-splitter-box class=vertical-splitter></div>
 <!-- Details box: This is the panel on the right which shows information -->
 <div id=events-view-details-log-box class="event-log content-box"></div>