Greasy Fork

This updated code seems to work without problems. However, please add var goTopButton = 1; back into the script. Why remove it when it was a functional part of the script?

Sorry that I didn't write the notice in English. The fact is that, the code, or the function that you mentioned, was not from me, but from another person, who took my code and modified while erasing my name from it and post a "new" script here, and deleted the script with that function when I asked that person to write my name and original script address in the script page. In simple words, I don't have that go-back-to-top function in my script. However, you can get it from the following script:
https://greasyfork.org/zh-CN/scripts/370556-%E4%B8%80%E4%B8%AA%E8%BF%94%E5%9B%9E%E9%A1%B6%E9%83%A8%E5%92%8C%E5%88%B0%E8%BE%BE%E5%BA%95%E9%83%A8%E7%9A%84%E6%8C%89%E9%92%AE