title: Why these tags are greyed out in firefox html source viewer?
body: <p><a href="https://i.stack.imgur.com/6TPHT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6TPHT.png" alt="enter image description here"></a></p>
  
  <p>I want to use beautifulsoup to get all these red-circle-marked li tags, but I can only get the first li tag,which is <code>&lt;li class="image item itemNo0 maintain-height" s...</code>
  (When the page is loaded, there's only the first li tag, and when I click the small thumbnails, li tags are created. After I click through all the small thumbnails in the left, three li tags are created, which is </p>
  
  <pre><code>&lt;li class="image item itemNo1 maintain-height" s...
  &lt;li class="image item itemNo2 maintain-height" s...
  &lt;li class="image item itemNo3 maintain-height" s...
  </code></pre>
  
  <p>so how to get these li tags?</p>
  
  <p>html:</p>
  
  <pre><code>    &lt;div class="a-text-center a-fixed-left-grid-col a-col-right" style="padding-left:1%;float:left;"&gt;
                  &lt;div class="a-row a-spacing-none a-grid-vertical-align a-grid-center canvas ie7-width-96" style="opacity: 1;"&gt;
                      &lt;div id="main-image-container" class="a-dynamic-image-container" style="height: 377px;"&gt;
  
      &lt;div id="video-outer-container"&gt;
          &lt;div id="main-video-container" class="chromeful-container"&gt;
          &lt;/div&gt;
          &lt;div id="video-canvas-caption" class="a-row"&gt;
              &lt;div class="a-column a-span12 a-text-center"&gt;
                  &lt;span id="videoCaption" class="a-color-secondary"&gt;&lt;/span&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;div class="a-hidden" id="auiImmersiveViewDiv"&gt;&lt;/div&gt; 
  &lt;div class="variationUnavailable unavailableExp" style="display: none;"&gt;
      &lt;div class="inner"&gt;
          &lt;div class="a-box a-alert a-alert-error" aria-live="assertive" role="alert"&gt;&lt;div class="a-box-inner a-alert-container"&gt;&lt;h4 class="a-alert-heading"&gt;Image Unavailable&lt;/h4&gt;&lt;i class="a-icon a-icon-alert"&gt;&lt;/i&gt;&lt;div class="a-alert-content"&gt;
              &lt;span class="a-text-bold"&gt;
                  Image not available for&lt;br&gt;Color:
                  &lt;span class="unvailableVariation"&gt;&lt;/span&gt;
              &lt;/span&gt;
          &lt;/div&gt;&lt;/div&gt;&lt;/div&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  &lt;ul class="a-unordered-list a-nostyle a-horizontal list maintain-height"&gt;
  &lt;li class="mainImageTemplate template"&gt;&lt;span class="a-list-item"&gt;
      &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
          &lt;div class="imgTagWrapper"&gt;
              &lt;span class="placeHolder"&gt;&lt;/span&gt;
          &lt;/div&gt;
      &lt;/span&gt;
  &lt;/span&gt;&lt;/li&gt;
  &lt;li class="swatchHoverExp a-hidden maintain-height"&gt;&lt;span class="a-list-item"&gt;
      &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
          &lt;div class="imgTagWrapper" style="height: 377px;"&gt;&lt;img src="https://images-na.ssl-images-amazon.com/images/I/912tYLsu2eL._SX425_.jpg" class="a-dynamic-image a-stretch-vertical" id="" style="max-height: 377px; max-width: 377px;" data-old-hires="https://images-na.ssl-images-amazon.com/images/I/912tYLsu2eL._SL1500_.jpg" data-a-manual-replacement="true"&gt;&lt;/div&gt;
      &lt;/span&gt;
  &lt;/span&gt;&lt;/li&gt;
  &lt;li class="image item itemNo0 maintain-height" style="cursor: pointer;"&gt;&lt;span class="a-list-item"&gt;
          &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
              &lt;div id="imgTagWrapperId" class="imgTagWrapper" style="height: 377px;"&gt;
                  &lt;img alt="6 Piece Hotel Luxury Soft 1800 Series Premium Bed Sheets Set, Deep Pockets, Hypoallergenic, Wrinkle &amp;amp; Fade Resistant Bedding Set(Full, Cream)" src="https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SX425_.jpg" data-old-hires="https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SL1500_.jpg" class="a-dynamic-image  a-stretch-vertical" id="landingImage" data-a-dynamic-image="{&amp;quot;https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SX466_.jpg&amp;quot;:[466,466],&amp;quot;https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SY450_.jpg&amp;quot;:[450,450],&amp;quot;https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SX522_.jpg&amp;quot;:[522,522],&amp;quot;https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SY355_.jpg&amp;quot;:[355,355],&amp;quot;https://images-na.ssl-images-amazon.com/images/I/91RE-nL%2BcYL._SX425_.jpg&amp;quot;:[425,425]}" style="max-width: 377px; max-height: 377px;"&gt;&lt;script type="text/javascript"&gt;if(typeof encodedImgSrc != 'undefined' &amp;&amp; encodedImgSrc != "" &amp;&amp; document.getElementById("landingImage")!= null){document.getElementById("landingImage").src=encodedImgSrc;};&lt;/script&gt;
              &lt;/div&gt;
          &lt;/span&gt;
      &lt;/span&gt;&lt;/li&gt;&lt;li id="noFlashContent" class="noFlash a-hidden"&gt;&lt;span class="a-list-item"&gt;
      &lt;hza:string id="softlines_dp_video_flash_player"&gt;
      &lt;a class="a-link-normal" target="_blank" rel="noopener" href="https://get.adobe.com/flashplayer"&gt;
          &lt;hza:string id="softlines_dp_video_flash_player_text"&gt;
          &lt;span class="swSprite s_extLink"&gt;&lt;/span&gt;
      &lt;/hza:string&gt;&lt;/a&gt;
  &lt;/hza:string&gt;&lt;/span&gt;&lt;/li&gt;
  &lt;li class="image item itemNo1 maintain-height" style="cursor: pointer;"&gt;&lt;span class="a-list-item"&gt;
      &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
          &lt;div class="imgTagWrapper" style="height: 377px;"&gt;
              &lt;img src="https://images-na.ssl-images-amazon.com/images/I/81pdBCFaeUL._SX425_.jpg" class="a-dynamic-image a-stretch-vertical" id="" style="max-height: 377px; max-width: 377px;" data-old-hires="https://images-na.ssl-images-amazon.com/images/I/81pdBCFaeUL._SL1500_.jpg" data-a-manual-replacement="true"&gt;
          &lt;/div&gt;
      &lt;/span&gt;
  &lt;/span&gt;&lt;/li&gt;&lt;li class="image item itemNo2 maintain-height selected" style="cursor: pointer;"&gt;&lt;span class="a-list-item"&gt;
      &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
          &lt;div class="imgTagWrapper" style="height: 377px;"&gt;
              &lt;img src="https://images-na.ssl-images-amazon.com/images/I/91y-xuiUG2L._SX425_.jpg" class="a-dynamic-image a-stretch-vertical" id="" style="max-height: 377px; max-width: 377px;" data-old-hires="https://images-na.ssl-images-amazon.com/images/I/91y-xuiUG2L._SL1500_.jpg" data-a-manual-replacement="true"&gt;
          &lt;/div&gt;
      &lt;/span&gt;
  &lt;/span&gt;&lt;/li&gt;&lt;li class="image item itemNo3 maintain-height" style="cursor: pointer;"&gt;&lt;span class="a-list-item"&gt;
      &lt;span class="a-declarative" data-action="main-image-click" data-main-image-click="{}"&gt;
          &lt;div class="imgTagWrapper" style="height: 377px;"&gt;
              &lt;img src="https://images-na.ssl-images-amazon.com/images/I/91cd38Ag0RL._SX425_.jpg" class="a-dynamic-image a-stretch-vertical" id="" style="max-height: 377px; max-width: 377px;" data-old-hires="https://images-na.ssl-images-amazon.com/images/I/91cd38Ag0RL._SL1500_.jpg" data-a-manual-replacement="true"&gt;
          &lt;/div&gt;
      &lt;/span&gt;
  &lt;/span&gt;&lt;/li&gt;&lt;/ul&gt;
  
  
  
  
  
  
  
  &lt;script type="text/javascript"&gt;
      var mainImgContainer = document.getElementById("main-image-container");
  
      var containerWidth = mainImgContainer.offsetWidth;
      var holderRatio = 1.0;
      var shouldAutoPlay = false;
      var containerHeight = containerWidth/holderRatio;
      containerHeight = Math.min(containerHeight, 700);
  
      var dynamicImageMaxHeight = 522 ;
      var dynamicImageMaxWidth = 522 ;
      var aspectRatio = dynamicImageMaxWidth/dynamicImageMaxHeight;
      var landingImage = document.getElementById("landingImage");
      var imgWrapperDiv = document.getElementById("imgTagWrapperId");
  
      var imageMaxHeight = containerHeight;
      var imageMaxWidth = containerWidth;
  
      if(!shouldAutoPlay) {
          imageMaxHeight = Math.min(imageMaxHeight, dynamicImageMaxHeight);
          imageMaxWidth = Math.min(imageMaxWidth, dynamicImageMaxWidth);
      }
  
  
      var useImageBlockLeftColCentering = false;
      var rightMargin = 32;
  
      if(typeof useImageBlockLeftColCentering !== "undefined" &amp;&amp; useImageBlockLeftColCentering){
          mainImgContainer.style.marginRight = rightMargin + "px";
      }
      mainImgContainer.style.height = containerHeight + "px";
  
      var imageMaxWidthBasedOnHeight = imageMaxHeight * aspectRatio;
      var imageMaxHeightBasedOnWidth = imageMaxWidth / aspectRatio;
      imageMaxHeight = Math.min(imageMaxHeight, imageMaxHeightBasedOnWidth);
      imageMaxWidth = Math.min(imageMaxWidth, imageMaxWidthBasedOnHeight);
  
      if(imgWrapperDiv){
          imgWrapperDiv.style.height = containerHeight + "px";
      }
  
      if(landingImage){
          landingImage.style.maxHeight = imageMaxHeight + "px";
          landingImage.style.maxWidth = imageMaxWidth + "px";
      }
  
      if(shouldAutoPlay){
          if(landingImage){
              landingImage.style.height = imageMaxHeight + "px";
              landingImage.style.width  = imageMaxWidth + "px";
          }
      }
  
  &lt;/script&gt;
  
  
  
  
  
  
                  &lt;/div&gt;
              &lt;div style="position: absolute; left: 50%; top: 50%; transform: translate3d(-50%, -50%, 0px); z-index: 3; width: 48px; height: 48px; border: 8px solid rgb(255, 255, 255); border-radius: 100%; display: none;"&gt;&lt;span class="a-spinner a-spinner-medium"&gt;&lt;/span&gt;&lt;/div&gt;&lt;/div&gt;
  
              &lt;div id="image-canvas-caption" class="a-row"&gt;
                   &lt;div class="a-column a-span12 a-text-center"&gt;
                      &lt;span id="canvasCaption" class="a-color-secondary"&gt;Roll over image to zoom in&lt;/span&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
  
              &lt;div class="collections-collect-button"&gt;&lt;/div&gt;
          &lt;/div&gt;
  </code></pre>
  
  <p>and <a href="https://rads.stackoverflow.com/amzn/click/com/B079S9XHMG" rel="nofollow noreferrer" rel="nofollow noreferrer">https://www.amazon.com/Premium-Pockets-Hypoallergenic-Wrinkle-Resistant/dp/B079S9XHMG/ref=sr_1_1_sspa?s=bedbath&amp;ie=UTF8&amp;qid=1522410001&amp;sr=1-1-spons&amp;keywords=sheets&amp;psc=1</a> is the web link I used to analylize.</p>