jQuery 1.4: a problem with interrupting ajax requests

I decided to switch to a new version, and here such an ambush. As you know, the $ .ajax () method returns an XMLHttpRequest object. This object has a .abort () method that interrupts the request. And here lies the difference from previous versions - before such an “underused request” was quietly dying, and in the new version the success event is triggered and underloaded pieces of code are inserted directly onto the page, which is why it all looks very not neat.

What is it, a bug or a new feature? How can this be circumvented? Help find the answer.

I could not find a normal changelog version that could bring clarity. And to see all the videos on jquery14.com in search of an answer, you know, is no good.