Why you might need two or more versions of Jquery on one page?

Repeatedly found a similar story and how they reconciled in the form of, for example, noConflict. Especially in wordpress. And why it might be needed? Alternatively, to ensure the operation of any old plugins? Or for something else?
June 8th 19 at 16:56
3 answers
June 8th 19 at 16:58
For bad code, of course
Seriously? Just met a really good-looking (at least externally) sites where ponameshano a lot of any questionable files scripts and a few (well, okay, usually not more than two) versions of jQuery. He just never felt the urgent need to connect two jQuery, so I thought, but not a fool length I? Maybe we should start?)) - Oleta96 commented on June 8th 19 at 17:01
absolutely

It's a symptom of that site are not pros, and random people

18 year, you have slowly forget that such a frame existed - marilyne_Roh commented on June 8th 19 at 17:04
and to write on pure js ? or is there something better / easier (I think this is important) jQuery ? - raheem.Homenic commented on June 8th 19 at 17:07
,
ES5, ES6, ES7

Easier will not be - marilyne_Roh commented on June 8th 19 at 17:10
,
you have gradually forget that such a frame existed

Especially considering the fact that he had never existed.

(Hint: jQuery is a library, not a framework) - Austen.Thompson53 commented on June 8th 19 at 17:13
true - marilyne_Roh commented on June 8th 19 at 17:16
June 8th 19 at 17:00
to support the existing functionality and the new.

the situations are different. for example, You have a working service, which was implemented in 13-14 year and You the current version and want to add something new and not write everything from scratch. And then connect several versions.
That is, if the website I created in 2018, the whole story noconflict and all sorts of migrate I don't need I don't need, right? - Oleta96 commented on June 8th 19 at 17:03
all noconflict need it in order to connect different versions. When the old code and too lazy to upgrade (or no budget), and the new whistles on the old core to start.
Migrate need it in the process of upgrading to a new version. When the part is updated, but not all. - marilyne_Roh commented on June 8th 19 at 17:06
and, that's how! you got it, thanks! - raheem.Homenic commented on June 8th 19 at 17:09
June 8th 19 at 17:02
For me personally, a year ago was a slider that worked in jquery 1.8 , but before I used to have a bunch of libraries which support jquery 1.13. So I had to put two versions. But it sucks to do so.

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