title: HTML cell does not combine height when used multiple rowspans
body: <p>I have a table with basic structure as below. The problem is when I use same rowspan for all the columns the height collapses to one row only.</p>
  
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;table border=1&gt;
    &lt;tr&gt;
      &lt;td&gt;1&lt;/td&gt;
      &lt;td&gt;2&lt;/td&gt;
      &lt;td&gt;3&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;4&lt;/td&gt;
      &lt;td&gt;5&lt;/td&gt;
      &lt;td&gt;6&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;7&lt;/td&gt;
      &lt;td&gt;8&lt;/td&gt;
      &lt;td&gt;9&lt;/td&gt;
    &lt;/tr&gt;
  &lt;/table&gt;</code></pre>
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  <p>when some of the columns have rowspans</p>
  
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;table border=1&gt;
    &lt;tr&gt;
      &lt;td rowspan=2&gt;1&lt;/td&gt;
      &lt;td rowspan=2&gt;2&lt;/td&gt;
      &lt;td&gt;3&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;6&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;7&lt;/td&gt;
      &lt;td&gt;8&lt;/td&gt;
      &lt;td&gt;9&lt;/td&gt;
    &lt;/tr&gt;
  &lt;/table&gt;</code></pre>
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  <p>When all the columns have rowspan. This is where the problem appears. Basically the expected result is for the first row to span two rows instead just one</p>
  
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;table border=1&gt;
    &lt;tr&gt;
      &lt;td rowspan=2&gt;1&lt;/td&gt;
      &lt;td rowspan=2&gt;2&lt;/td&gt;
      &lt;td rowspan=2&gt;3&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;7&lt;/td&gt;
      &lt;td&gt;8&lt;/td&gt;
      &lt;td&gt;9&lt;/td&gt;
    &lt;/tr&gt;
  &lt;/table&gt;</code></pre>
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