Steps to Reproduce

1. Open https://keikai.io/demo/excel_like.
2. Press Ctrl-C or Command-C in cell B8.
3. Copy area selection did not show up.

Current Result

Expected Result

Debug Information

1. Test in Chrome in MBPR.
2. Click "Copy" in the context menu is OK.
3. If I create a new sheet, Ctrl-V will show copy area

Workaround