Haven't heard about this bug in a while.
i am stuck "moonwalking"
This probably happens when you switch tabs in browser (at least this happened to me, many, many times), the game thinks you're just moving your character, because you left it suddenly, probably while running. You can stop it by pressing the button of the direction that the character is moving, as Aleks said.
Just press the button that your character is moving. For example, my character is stuck moving right, so then I press the button that makes me move right and then I'll stop constantly moving in one direction. This also works when you're moving diagonally, the only difference being you have to press two keys. I don't think this is fixable because it happens in every game that uses arrow keys or WASD.
I think the problem is probably fixable, it's just hard to fix.
Stop bumping threads >:(
Ami happens to me, sometimes I have the character walking towards a direction, it started to happen yesterday
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