Error: I did not use the ++ symbol

[Zeng0o]

Challenge Increment a Number with JavaScript has an issue.
User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36.
Please describe how to reproduce this issue, and include links to screenshots if possible.

My code:

var myVar = 87;

// 请只修改这条注释以下的代码
myVar = ++myVar;

[FEILELAI]

a = myVar++;