Hi @DUVAL Joffrey ,
Welcome to our forum!
As i know, the functionality and appearance of New Outlook is similar to that of the Outlook web app. For the Advanced editor options as you mentioned, i'm afraid that it's not available in New Outlook. To use this function, it's suggested that you could turn off New Outlook button to switch to Legacy Outlook.
Please kindly understand that many functions are not designed at present. It is recommended that you could post the functions you expect and your sincere suggestions on the website dedicated to collecting feedback. We sincerely welcome your suggestions, and thanks for your understanding and support!
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