Running an effect only on update vs Strict mode

I have written a variation of the useEffect hook that should only run on updates. I used a useRef hook to accomplish this the way the FAQ in the old docs recommends it here:

I couldn't find the same piece in the new documentation.

The problem is that the effect still runs on the initial render when strict mode is on:
https://codesandbox.io/s/delicate-lake-88phjz?file=/src/App.js

however it behaves correctly when the strict mode is off:
https://codesandbox.io/s/hungry-wright-tl7p43?file=/src/App.js

In the former example the message is logged to the console right away even though it shouldn't be.

The possible explanations I can think of are:

1. I'm doing something wrong. Can you please point the mistake out for me?
2. The old docs are off and this is not the right way to do it. In this case can you please let me know what the right way of achieving this behavior is?
3. The strict mode is to blame. I do find it irritating at times, if I'm frank, but that's probably unlikely.

Can someone help me with this? Thanks a lot!

先在連結的兩個 CodeSandbox 範例中重現該行為，並比較 Strict Mode 與非 Strict Mode 的情況。將舊的 FAQ 摘錄與目前的 useEffect 和 useRef 文件一併閱讀；當清楚記錄跳過初始 render 的 effect 所建議的行為，或將 issue 解釋為預期的 Strict Mode 行為時，即可視為完成。