title: boostrap-vue when using tabs in modal it is not working properly
body: <p>If you put b-tabs inside of a modal, upon opening the modal for the first time everything works fine, but if you close the modal and reopen it, then the tabs don't work, it will be stuck on the content of the first tab, and switching tabs will not have any effect, instead the content of the first tab will remain visible. Reloading the page is the only way to get it to work again.</p>
  
  <p>Visit <a href="https://jsfiddle.net/gh9y7zLs/2/" rel="nofollow noreferrer">https://jsfiddle.net/gh9y7zLs/2/</a> to reproduce the problem</p>
  
  <pre><code>    &lt;div id='app'&gt;
  &lt;div&gt;
      &lt;b-button v-b-modal.modal1&gt;
        Launch demo modal
      &lt;/b-button&gt;
  
      &lt;!-- Modal Component --&gt;
      &lt;b-modal
        id="modal1"
        title="BootstrapVue" &gt;
        &lt;b-tabs content-class="mt-3" v-model="tabIndex"&gt;
          &lt;b-tab
            title="first"
            active
          &gt;
            I'm the first fading tab
  
            &lt;b-button v-b-modal.modal1 @click="next()"&gt;
              Next
            &lt;/b-button&gt;
          &lt;/b-tab&gt;
          &lt;b-tab title="second"&gt;
            &lt;p&gt;
              I'm the second tab content
            &lt;/p&gt;
          &lt;/b-tab&gt;
          &lt;b-tab
            title="disabled"
            disabled
          &gt;
            &lt;p&gt;
              Disabled tab!
            &lt;/p&gt;
          &lt;/b-tab&gt;
        &lt;/b-tabs&gt;
      &lt;/b-modal&gt;
  
    &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>Anyone have a solution ?</p>