You can perform zoom operations on the Construction Canvas.
For fixed-ratio X/Y zoom, drag the slider at the top of the Canvas. Dragging it to the left shrinks the view while keeping the X/Y ratio fixed; dragging it to the right enlarges it.
For variable X/Y zoom, right-click and hold on the Canvas, then move the mouse in any direction. Moving to the left along the X axis or upward along the Y axis shrinks the view. Moving to the right along the X axis or downward along the Y axis enlarges it. The ratio between the X-direction zoom and the Y-direction zoom is determined by the ratio between the X and Y components of the mouse's movement direction (speed).
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