title: Make CSS: "resize: horizontal" work with Mat-Table on firefox
body: <p>I have a mat-table and wanted to make the columns resizeable, so I stumbled across the CSS property "resize" which works perfectly well for regular HTML tables</p>
  
  <p>Basic HTML: </p>
  
  <pre><code> &lt;table id="main_table"&gt;
            &lt;tr class="header"&gt;
              &lt;td&gt;&lt;div class="tableHeaderCellDiv"&gt;Tech Name&lt;/div&gt;&lt;/td&gt;
              &lt;td&gt;&lt;div class="tableHeaderCellDiv"&gt;Name&lt;/div&gt;&lt;/td&gt;
             &lt;/tr&gt;
     &lt;/table&gt;
  </code></pre>
  
  <p>CSS: </p>
  
  <pre><code>.tableHeaderCellDiv { resize: horizontal;  overflow:hidden;}
  </code></pre>
  
  <p>Which gives the headers a very nice box with which you can resize the columns.
  However, when trying to bring this exactly same thing over to my mat-table, the drag-box simply didn't show up.</p>
  
  <pre><code>&lt;table mat-table [dataSource]="items" class="mat-elevation-z8"&gt;
    &lt;ng-container [matColumnDef]="column" *ngFor="let column of displayedColumnsMAT"&gt;
      &lt;th mat-header-cell class="custom-mat-header-styling tableHeaderCellDiv" *matHeaderCellDef&gt;{{column}}&lt;/th&gt;
    &lt;/ng-container&gt;
  
    &lt;tr mat-header-row class="tableHeaderCellDiv" *matHeaderRowDef="displayedColumnsMAT; sticky: true;" &gt;&lt;/tr&gt;&lt;!-- for the header row --&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>I've cut out the not-header-rows for both examples, as they don't matter for now.
  I've also tried inserting tableHeaderCellDiv (same CSS as for the plain HTML) as a class everywhere, guessing that that is the problem.</p>
  
  <p>What am I doing wrong, or could it be that that feature simply does not work at all with Mat-Tables?</p>
  
  <p><strong>[EDIT:]</strong> thanks to @KrishnaRathore I now know that my code (probably) isn't the problem but Firefox is. If you're content with Chrome check out his answer though, it works.</p>
  
  <p><strong>HOWEVER</strong>, this problem seems to be unique to Mat-Table, as there is another small plain HTML table in my project with which the resizing works fine.</p>