-<p>A row of annotation is added with a line like <strong><pre><em>GRAPH_TYPE</em>	<em>Label</em>	<em>Values</em></pre></strong></p>
-<p>The <em>GRAPH_TYPE</em> field, which appears first, defines the
-appearance of the annotation row when rendered by Jalview. The next field is the row label for the annotation. The final <em>Values</em> field contains a series of "|"
-separated value fields. Each value field is itself a comma separated list of fields of a particular type defined by the annotation row's
-GRAPH_TYPE. The allowed values of GRAPH_TYPE and the format of their respective value fields (with the trailing "<strong>|</strong>" symbol) are shown below:<ul>
- <li>BAR_GRAPH<br>
- Plots a histogram with labels below each bar.<br>
- <em>number</em>,<em>text character</em></li>
- <li>LINE_GRAPH<br>
- Draws a line between values on the annotation row.<br>
- <em>number</em></li>
- <li>NO_GRAPH<br>
- For a row consisting of text labels and/or secondary structure symbols.<br>
- <em>{Secondary Structure Symbol}</em>,<em>text label</em><br>
- Currently supported secondary structure structure symbols are <em>H</em> (for helix) and <em>E</em> (for strand)</li>
-</ul>
-Any or all value fields may be left empty, as well as the BAR_GRAPH's
+<p>A row of annotation is added with a line like <strong><pre><em>GRAPH_TYPE</em>	<em>Label</em>	<em>Description</em> (optional)	<em>Values</em></pre></strong></p>
+ <p>
+ The <em>GRAPH_TYPE</em> field, which appears first, defines the
+ appearance of the annotation row when rendered by Jalview. The next
+ field is the row <em>label</em> for the annotation. This may be
+ followed by a <em>description</em> for the row, which is shown in a
+ tooltip when the user mouses over the annotation row's label. Since
+ Jalview 2.7, the description field may also contain html in the same
+ way as a <a href="featuresFile.html">sequence feature's</a> label,
+ providing the html is enclosed in an <html/> tag.
+
+ <ul><em>Please note: URL links embedded in HTML descriptions will
+ be supported in a future release of Jalview</em>
+ </ul>
+ </p>
+ <p>The final <em>Values</em>
+ field contains a series of "|" separated value fields. Each
+ value field is itself a comma separated list of fields of a particular
+ type defined by the annotation row's GRAPH_TYPE. The allowed values of
+ GRAPH_TYPE and the format of their respective value fields (with the
+ trailing "<strong>|</strong>" symbol) are shown below:
+
+ <ul>
+ <li>BAR_GRAPH<br> Plots a histogram with labels below each
+ bar.<br> <em>number</em>,<em>text character</em>,<em>Tooltip
+ text</em>
+ </li>
+ <li>LINE_GRAPH<br> Draws a line between values on the
+ annotation row.<br> <em>number</em>
+ </li>
+ <li>NO_GRAPH<br> For a row consisting of text labels and/or
+ secondary structure symbols.<br> <em>{Secondary Structure
+ Symbol}</em>,<em>text label</em>,<em>Tooltip text</em><br> Currently
+ supported secondary structure structure symbols are <em>H</em> (for
+ helix) and <em>E</em> (for strand)</li>
+ </ul>
+ Any or all value fields may be left empty, as well as the BAR_GRAPH's