Microsoft will globally remove the Copilot theme feature from new Outlook across all platforms by mid-to-late October 2026 due to low user adoption. The auto-summarize function is also being discontinued. Instead, Microsoft is shifting focus to a chat-centric design, prioritizing practical AI task assistance over interface customization. This strategic pivot aims to enhance user productivity by integrating Copilot directly into the chat window, replacing aesthetic features with functional assistant capabilities to better justify development investments and meet user needs.