Search finds a message, a canvas or a list by every word you type, small ones included: “deploy is blocked”, “Q3 plan” and “the Roadmap” used to find nothing.
Pause notifications until it clears now works with a status scheduled for later: the pause starts when the status shows and ends when it clears. Cancelling it while it shows, or clearing your status early, ends the pause too.
A poll, a Link that starts, a mention, a reply in a thread you follow, and a private channel you are added to now appear while you look, in the channel, in Activity, in Threads and in the sidebar. A channel somebody else makes is no longer drawn in your sidebar until you join it.
With people from a connected organization: New message finds the person you already have a conversation with, the DMs page names their organization, and a closed conversation offers nothing it would refuse. Only the controls that work there are offered, in the conversation and in channels shared with you.