@leocg Yes, I did all the things like in the "https://forums.opera.com/topic/43601/instructions-on-posting-about-problems-in-opera-for-windows/2", but it still can not show pdf file correcttly.
My OS is windows 10 21H2 64 bit, the ver of opera is 87.0.4390.45.
The problerm web page link is "https://www.analog.com/media/en/technical-documentation/data-sheets/adl5580.pdf".
The screen-shot of the problerm is 
BTW, when I drop a local pdf file to opera, it also can not show it's content correcttly.
But as I mentioned before, when I install the old ver 85.0.4341.18 of opera, it did well all about those pdf files.