Today I ran into the specific MahJax problem for which I cannot find the cause.
Interestingly, if this Mathjax syntax somehow works in the Q&A area, it definitely doesn't work in the comment section. (I tried many times)
Now one more interesting problem than that is that the MathJax syntax I mentioned works "completely randomly" without my intervention, or it doesn't work. The only thing I can do is refresh the page $10-15$ times.
As soon as the specific Mathjax syntax I mentioned runs, if the page is refreshed, unfortunately syntaxis won't work again.
Here is the MathJax syntax that "randomly works or doesn't work":
Well here it didn't work either...
Here are the images I took:
What is the source of the problem? I am not a computer user.