Error when editing source code using a code editor.

[Duynguyen0897]

Below are two examples: one example of an error when modifying text, and one example when copying the source code and pasting it into another box, then editing the copied source code causes the original source code to be changed as well.

[givanz]

Thanks for the bug report, it's fixed in the last commit 06eb349

[Duynguyen0897]

Thanks @givanz