Rounding a rectangle shifts its location

See the simple demonstrtion at https://www.khanacademy.org/computer-programming/wat3/6754888494743552

If you specify a fifth argument to rect, the location of the rendered rectangle is shifted, even when the value of the fifth argument is zero.

The problem lies within Processing.js. Do you have a conduit to their bugs database?

Start by reproducing the behavior in the linked Khan Academy demonstration, comparing rect calls with and without a fifth argument, including zero. Trace the rectangle rendering path in Processing.js and verify that supplying the fifth argument no longer shifts the rendered location.

Written by the indexing model from the issue text.