Hi @Thomas ,
Welcome to our forum!
Based on my research, i didn't find related settings as you mentioned in Outlook for web. I'm afraid that it is not available in Outlook for web.
Please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. At present, what I can do for you is to submit feedback for your request and I have post here, and you could vote for it. If you have any suggestions or ideas, it's suggested that you could post here. Hope Microsoft will notice this in the future.
In addition, if you need help of Outlook Android App, it's suggested to post your issue on this dedicated forum for Outlook for Android for more professional help.
Thanks for your understanding and support!
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