Webview - back button bug

My webview app displays ,,hello world'' text.

I open it, and close shortly after with back button (without deleting from recently opened apps): http://pastebin.com/bAhqqYPS

Then, I try to open it again (from ,,desktop'', or how to call it), and it crashes with segmentation error: http://pastebin.com/uH22kSUV

I use python 2 for this app.
