Spotify recently decided to change the default of whether a user is sharing their activty or not. This update doesn't actually solve the issue that the activity toggle is hard to find and unknown by a large majority of users.
My suggestion is to place a toggle and indicator at the top of the 'Friend Activty' sidebar so that users can turn on and off their activty sharing with ease and be aware of their sharing status. This will not totally resolve the issue because a user will need to have the 'Friend Activity' sidebar enabled to see it to start with but it is a start to making this functionality far more accessible and obvious.
An additional change would be to place a 'Share Activty with Friends' button under the 'Private Session' button in the profile dropdown menu with a green check mark to it when enabled similar to what the 'Private Session' button does when enabled. If this is done it is important to make it clear in the settings menu and possibly through hints what the difference is between enabling a private session, and disabling sharing your activity.
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