At first, I would like to thank you so much for correctly explaining the causes of the problem to the xn__p2a habrauser and to apologize to other habrauser for some incompetence in the question that took place.Probably, all users of this browser have repeatedly encountered the following problem: when trying to download a file, we get the following:

Once again, I caught this bug when I wanted to download the flash player via only Opera 10.60 supplied and it upset me a lot ...
Who is guilty?
Such a thing as
mime type is responsible for the type of content sent to the web server by the browser. Looking at the mime type, the browser must determine what to do with the downloaded file. This type is transmitted by the web server in HTTP headers, namely in the
content-type: line . By default, Opera believes the server headers, but for unclear reasons, they are trying to stick the wrong mime type specifically to Opera. The browser strictly follows the standards and acts according to the type of data provided to it.
- The point is to wean the opera to believe all sorts of bad servers and act according to the extension of the downloadable file.
The “trust server types” parameter is responsible for this, which does just the opposite and when true, the opera DOES NOT trust the servers, but looks at the file extension (the reasons for such irrationality are still not clear to me), and that’s what we need.
What to do?
- Go here: "opera: config # trust server types" (just paste it into the address bar without quotes)
- Put a tick, click save.
We admire the result:

Thank you all for your attention, good luck!