The arrow (in the folder/subfolder list) is missing in Vue3. It appears only after refreshing the page. 

How to reproduce : 
1) Create a new folder with no file inside
2) Create a new subfolder with no file inside
3) Validate the creation with the Validate button (and not with the Enter key)
4) Check that the arrow is missing in "Fichiers" list (red circle on the screenshot below)