title: ngx-bootstrap dropdown not opening angular 4 bootstrap 4
body: <p>I can't figure out what's going on here - I've included ngx-dropdown code that I believe is correct based on documentation:</p>
  
  <p><strong>home.component.html</strong></p>
  
  <pre><code>    &lt;div class="btn-group" dropdown&gt;
        &lt;button dropdownToggle type="button" class="btn btn-primary dropdown-toggle"&gt;
          Button dropdown &lt;span class="caret"&gt;&lt;/span&gt;
        &lt;/button&gt;
        &lt;ul *dropdownMenu class="dropdown-menu" role="menu"&gt;
          &lt;li role="menuitem"&gt;&lt;a class="dropdown-item" href="#"&gt;Action&lt;/a&gt;&lt;/li&gt;
          &lt;li role="menuitem"&gt;&lt;a class="dropdown-item" href="#"&gt;Another action&lt;/a&gt;&lt;/li&gt;
          &lt;li role="menuitem"&gt;&lt;a class="dropdown-item" href="#"&gt;Something else here&lt;/a&gt;&lt;/li&gt;
          &lt;li class="divider dropdown-divider"&gt;&lt;/li&gt;
          &lt;li role="menuitem"&gt;&lt;a class="dropdown-item" href="#"&gt;Separated link&lt;/a&gt;
          &lt;/li&gt;
        &lt;/ul&gt;
      &lt;/div&gt;
  </code></pre>
  
  <p><strong>app.module.ts</strong></p>
  
  <pre><code>@NgModule({
    imports: [
      BsDropdownModule.forRoot(),
      ...
      ]
  </code></pre>
  
  <p><strong>site.module.ts</strong> (this is the module that contains the home component)</p>
  
  <pre><code>@NgModule({
    imports: [
      BsDropdownModule,
  </code></pre>
  
  <p>I'm using angular-cli and I've included the bootstrap style:</p>
  
  <pre><code>    "../node_modules/bootstrap/dist/css/bootstrap.min.css",
  </code></pre>
  
  <p>and in <strong>index.html</strong> I've added a snippet to let the browser know I'm using bootstrap 4:</p>
  
  <pre><code>&lt;script&gt;window.__theme = 'bs4';&lt;/script&gt;
  &lt;app-root&gt;Loading . . .&lt;/app-root&gt;
  </code></pre>
  
  <p>The button appears, and there are no errors shown in the console.  I can see the dom changing when I click the button ("open" and "show" are being added to the styles).  But nothing below the button opens up - no menu is shown.</p>
  
  <p>I don't know where else to look </p>