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The rename option has been moved to the gadget menu, which has its own toolbar button, as explained below.
The gadget menu is a drop-down menu that appears when you click on the \ [\] icon in the gadget toolbar. Wiki Markup
Basic gadget editing functionality - such as the ability to rename the gadget, which was available as a toolbar option in previous versions of the dashboard - is accessible using this menu. Additionally, the gadget-specific functionality visible in the new gadget toolbar is available here as well in an easy-to-read list format.
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