Knowing which WordPress theme uses a web is quite easy, and we have already seen several other methods of guessing it on other occasions, but for to know what WordPress plugins use is a bit more complicated, but still possible.
One of the easiest ways to find out is through an extension, available for Chrome and Firefox browsers ]that within its analysis of websites, if it is a WordPress, in addition to the theme, also lists the plugins that it uses .
I mean SpyBar, an extension that, although it is not free, for the professional really interested in discovering those little secrets, it can be a great investment. In addition, the price is not that it is excessive, because for only 12.95 $ you have it up and running with a lot of features, not only detect plugins and WordPress themes . ] Perfect is not, everything has to be said, because it does not make us list all the plugins that the site uses, but if it detects a good amount of them.
Surely you're already thinking that you can also detect them by identifying specific CSS classes and references in the code but it's much more tedious and slow, you will not deny that to me.
So yourself, but existing exists, and works quite well.
This video explains the possibilities of extension …
I knew about this extension on WPjedi