Hi @Liam Briars ,
Do you mean the Edit Message option on the ribbon?
According to my research and test, currently there is no option to edit message in new outlook. The new Outlook is not yet complete, and some options may not be available or work as expected.
As a workaround, you can switch back to the classic Outlook by clicking the toggle button in the top right corner of the window.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future, and you can make a suggestion via this link
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