Hi @BODENSTAB Kristina ,
I'm sorry that brought you a bad experience, Conditional Formatting is currently not supported in New Outlook for Windows, and this work is in progress and will be available in the future.
The new Outlook is not yet complete and some options may not be available or work as expected, we recommend you stay in the classic Outlook until they are resolved, or you can switch the toggle to go between apps as often as you want.
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. Microsoft collected this feedback, and you can also vote via this Conditional formattting support
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