Probably the best way to achieve this:
1. Create new graph widget
2. In host pattern data set, add about 50-10 spaces
3. Press add and receive error.
4. Click again in host pattern field and add a few new lines
5. Press add and receive error.
6. Double click mouse in the first line where spaces are somewhere in the middle so that the field is in focus and blinking cursor is not visible. if this does not happen, keep trying till this occurs.
7. Press backspace to delete spaces and new lines.
8. Observe that browser wants to leave this page.