Hi YM,
Thank you for sharing your feedback. I understand that it can be inconvenient when a familiar feature, such as the Select All checkbox, is no longer available in the New Outlook experience.
Based on my testing, New Outlook no longer includes the traditional Select All checkbox above the message list. Instead, you can select all emails in the current folder or view by:
- Clicking the Select option above the message list and choosing the available selection options.
- Pressing Ctrl + A on your keyboard to select all emails in the current folder/view.

I truly appreciate you sharing your feedback because your issue is thoughtful, practical, and reflects a real need that many users likely share. Ideas like this play an important role in improving the product experience.
To ensure your voice reaches the right team, I highly encourage you to submit your feedback directly through the Outlook (new) · Community portal. This is the most effective way to ensure your voice reaches the product team and can be considered for future improvements.
As community moderators, we kindly ask for your understanding that our access to internal development details is limited. Our primary role is to guide users toward the appropriate resources and support channels. While we may not have influenced product design decisions and have limited access to internal development details, we’ll continue doing our best to support you within the scope of our responsibilities.

Once you've submitted your feedback, feel free to share the link here in the comments. I’ll be happy to upvote it to help bring more visibility. If you prefer, I can also submit this great idea on your behalf. Just let me know, and I’ll post it for you and share the link once it’s published. I’m here to help ensure your feedback gets the attention it deserves.
Additionally, as other users have raised similar concerns and may not be aware of where to share their feedback, I hope this response helps clarify the situation and suggests a potential next step. Highlighting this information can make it more visible to others in the community who may be facing the same issue, making it easier for them to find guidance and contribute their feedback as well.
Thank you again for your time and for raising this important usability concern.
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