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Selecting Layout Variants
When there are one or more variants for a layout, you can select it from the first drop-down list left of the [Actions] button. For example:
Expand the drop-down and select the variant you want to add to the canvas.
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Switching Layouts
After selecting a layout, you can switch to another using the drop-down to the left of the Layout Variant drop-down. For example:
Expand the drop-down and select the layout you want to add to the canvas.
Layout Switching Logic
Depending on the circumstances under which you switch to another layout and what you've already done in the layout you're switching from, there are a number of possibilities that can occur.