Start a one-player game with no bots on scenario 1.
Click on the "Next Action" button until you get vortex.
Click on a hero and hold down the button and move wildly in and out of the browser window several times.
Open the browser debugger's console and you should see some errors.
Production:
Uncaught TypeError: o.default.get(...).isEmpty is not a function
at e.value (bundle.js:1)
at e.value (bundle.js:1)
at Object.mouseMove (bundle.js:1)
at e (bundle.js:1)
Local Development:
Uncaught TypeError: targetCell.isEmpty is not a function
at Hero.getPath (hero.js:100)
at Hero.checkPath (hero.js:182)
at Object.mouseMove (events.js:301)
at draw (user.js:90)
Production:
Local Development: