[BUG]Editing story: can't edit value. #544

Describe the bug

In editing story, I can't edit cell values.

To Reproduce

Steps to reproduce the behavior:

1. Go to editing story
2. Double click on "First value" or "Second value". (Nothing happens)

Expected behavior

Double-click the text to make it editable.
mxgraph example

maxgraph@0.13.0

Additional context

I've used editing in my personal projects, so perhaps it's just a problem with the story.