A simple Google Image search will show a lot of icons related to "Undo & Redo", and interestingly, most of them, if not all are round. Take a look at the ones Microsoft Office uses: And some o
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editor - Why are the Undo and Redo arrow icons commonly round? - User Experience Stack Exchange
editor - Why are the Undo and Redo arrow icons commonly round? - User Experience Stack Exchange
Undo/Redo icons are too similar to Reload icon · Issue #293 · ant-design/ant-design-icons · GitHub
Does a rollover that replaces content with an icon help user understand the role of a button? - User Experience Stack Exchange
editor - Why are the Undo and Redo arrow icons commonly round? - User Experience Stack Exchange
material design - Cross or left arrow to return to the previous page? - User Experience Stack Exchange
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