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Press the '…' button on the canvas toolbar Canvas Toolbar and then select Save session.
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Enter the name YouTube for the session name. You will be able to reload the layer at a later date by selecting this session. (If a session with same name already exists, a dialog box will be displayed with suitable options.)
Next select New session from the same menu. This will remove all unpinned layers and the Canvas Toolbar will still be accessible on the canvas.
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