How to reproduce

• connect to bo
• add an animated gif in the ressource explorer
• edit a content
• add an html expert to display the gif, for example

  <img width="650" class="invisible floatright" alt="Ametys Intranet & Collaboratif" src="${type:attachment-content#url:resource://5713b3aa-e732-4181-b5a5-9f4bb8ce640d#download:false}">
  

• save

*Actual behavior

• the gif is not animated, it seems that it is due to a recent improvements to take care about JPG rotation, all the ressources are generated by Ametys. You should exclude GIF