Clearer verbiage of where the file is being stored when attaching to a chat or conversation
When you 'attach' a file to a chat or conversation, make some kind of quick balloon or label that points out that:
1. The file shared in chat was put in your OneDrive under ad "teams chat" folder it has created and auto-shared the file with your chat partner(s)
2. The file shared in a conversation was put into the channels Files tabs and linked to in the message you're composing
This helps people comprehend what is happening when they "attach" - all too often people think that deleting the conversation or chat is deleting the file - and it isn't. If they know that the file is separate from the chat/conversation, it would make that a bit more obvious.
Maybe even a pop up when you're deleting a chat/conversation: "You're message has a share link to your OneDrive/Channel's files - do you want to delete the associated file when deleting this message?"