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In Fences 5, this feature can be found under the “Hide” tab of your Fences Configuration application:
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Older Other versions of Fences will may have the quick-hide setting located under the “Vanish” or “Quick-hide” tab:
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If this does not help, please make sure you have not inadvertently put the Fence on an alternate “desktop page” using Pages. Ensure Pages is disabled to see if the Fence \ Icon returns to your main desktop:
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