title: Groupbox visibility toggles between two but not third groupbox
body: <p>I'm creating a WindowsFormApp that has a Menu Strip that contains three options. What I want to do is have 3 groupboxes, though only one being Visible at start and when the respective option has been clicked in the MenuStrip, it toggles between the 3 groupboxes by toggling their visibility. Right now groupbox1 is visible on the start of the program but I can only then toggle between groupbox2 &amp; groupbox3. Once I switch to groupbox2 or groupbox3, I can no longer switch back to groupbox1.</p>
  <p>Here is a minimal code of what I've done so far:</p>
  <pre><code>        private void show1ToolStripMenuItem_Click(object sender, EventArgs e)
          {
              groupBox1.Visible = true;
              groupBox2.Visible = !groupBox1.Visible;
              groupBox3.Visible = !groupBox1.Visible;
  
          }
  
          private void show2ToolStripMenuItem_Click(object sender, EventArgs e)
          {
              groupBox2.Visible = true;
              groupBox1.Visible = !groupBox2.Visible;
              groupBox3.Visible = !groupBox2.Visible;
          }
  
          private void show3ToolStripMenuItem_Click(object sender, EventArgs e)
          {
              groupBox3.Visible = true;
              groupBox1.Visible = !groupBox3.Visible;
              groupBox2.Visible = !groupBox3.Visible;
          }
  </code></pre>
  <p>I have already created items in groupboxes and set groupbox1 visibility to true while 2 and 3 remains false.</p>