title: How to migrate content after Switching default language in TYPO3?
body: <p>I have site with multi domain and having multi-language Italian and English in TYPO3 8.7.4. Now, before switching language my default language was English
  here is configuration for this:</p>
  
  <p>:: config ::</p>
  
  <pre><code>language = en
  locale_all = english
  sys_language_mode = content_fallback
  htmlTag_langKey = en
  sys_language_uid = 0
  
  #Language configuration
  [globalVar=GP:L=1]
      config{
          language = it
          locale_all = italian
          sys_language_mode = content_fallback
          htmlTag_langKey = it
          sys_language_uid = 1
      }
  [global]
  </code></pre>
  
  <p>:: Backend Mod ::</p>
  
  <pre><code>mod.SHARED {
      defaultLanguageLabel = English
      defaultLanguageFlag = en
  }
  </code></pre>
  
  <p>Now, I want to change my TYPO3 site default language from English to Italian. So, I have done revert configuration like this:</p>
  
  <p>:: config ::</p>
  
  <pre><code>language = it
  locale_all = italian
  sys_language_mode = content_fallback
  htmlTag_langKey = it
  sys_language_uid = 1
  
  #Language configuration
  [globalVar=GP:L=1]
      config{
          language = en
          locale_all = english
          sys_language_mode = content_fallback
          htmlTag_langKey = en
          sys_language_uid = 0
      }
  [global]
  
  :: Backend Mod ::
  
  mod.SHARED {
      defaultLanguageLabel = Italian
      defaultLanguageFlag = it
  }
  </code></pre>
  
  <p>Now, I have issue with my existing content. How to migrate this content. It shows incorrectly. While I add content in Italian language it shows in English language. How can I fix this?</p>