为何Python Turtle模块中鼠标跟随的海龟会出现偏移？

我正在编写一个让海龟（turtle）跟随鼠标移动的程序，当前代码如下：

import turtle

t = turtle.Turtle()

canvas = turtle.getcanvas()
width = canvas.winfo_width()
height = canvas.winfo_height()

midpointX = width / 2
midpointY = height / 2

t.speed(0)

while True:
    mouseX, mouseY = canvas.winfo_pointerxy()

    turtleX = mouseX - midpointX
    turtleY = (mouseY - midpointY) * -1 

    t.goto(turtleX, turtleY)

在PyCharm或命令行运行时海龟会出现偏移，但在Replit上运行则无此问题，我使用的是Windows 11系统。当鼠标位于屏幕边缘时，海龟的移动范围如图所示：

内容的提问来源于stack exchange，提问作者sbottingota