Replied 8 September 2017, 3:23 pm EST
If you copy a cell value which contains an embedded double-quote character, and the cell is not in edit mode, then Spread will automatically wrap the contents of that cell with double-quotes, and insert an additional double-quote after the embedded one inside the string. On pasting, if the value on the clipboard is wrapped inside double-quotes, then the paste logic should remove the extra double-quote inserted (convert all instances of two consecutive double-quote characters into one) and strip off the double-quotes around the value (at the start and end).
Excel works the same way -- if you type a value containing a double-quote in a cell and copy/paste it to Notepad (not in edit mode), then you should see the raw value pasted in Notepad as Excel puts it on the clipboard, exactly like Spread -- resulting in "3""" in this case, like in your picture. But if you paste that value into Excel (or into Spread), not in edit mode, then it should paste the value as just 3" (as it appears in the source cell).
If you need to use Clipboard.GetText(), then you will need to handle this parsing logic in your code before setting the text to the cell.