title: TYPO3 8.7 can not override Fluid Styled Content templates
body: <p>I've tried to override the Fluid Styled Content elements but it doesn't work at all in latest TYPO3 version 8.7.0.</p>
  
  <p>I've got a template extension (key: biv_main) in which I add my overriding template pathes:</p>
  
  <pre><code>lib {
  fluidContent {
          templateRootPaths {
              30 = EXT:biv_main/Resources/Private/Content/fluid_styled_content/Templates/
          }
          partialRootPaths {
              30 = EXT:biv_main/Resources/Private/Content/fluid_styled_content/Partials/
          }
          layoutRootPaths {
              30 = EXT:biv_main/Resources/Private/Content/fluid_styled_content/Layouts/
          }
      }
  }
  </code></pre>
  
  <p>The TypoScript in the Backend via TS Object Browser looks correct to me:
  <a href="https://i.stack.imgur.com/3XuXh.png" rel="noreferrer">Screenshot TypoScript object browser - lib.fluidcontent</a></p>
  
  <p>I have copied the whole template, partial and layout folder with every file in it from sysext fluid_styled_content, so that every content element should be overridden.</p>
  
  <p>This is my folder structure in the template extension:</p>
  
  <pre><code>biv_main
  -- Resources
    -- Private
      -- Content
        -- fluid_styled_content 
          -- Layouts
          -- Partials 
          -- Templates
  </code></pre>
  
  <p>In the folders are exactly the same files as in sys-ext fluid_styled_content/Resources/Private/</p>
  
  <p>The static typoscript template for Fluid Content Elements are loaded before the template extension biv_main.</p>
  
  <p>Do you have any ideas or a clue what's missing and why it's not working?</p>