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Control widget areas on a per-page / per-post basis.
Gives you the ability to show or hide individual widget areas on each page / post as well as completely substituting the widgets shown in a specific widget area on a specific page or post.
<h3>Compatibility</h3>
The plugin has not been tested below version 3.3.

Per Page Widgets

Control widget areas on a per-page / per-post basis.

Andrico

A wonderful plugin to easily create many custom sidebars. These sidebars can then select in the creation of a post / page / custom post type / category / taxonomy. We give an order, and select several at once. 
You will see all active sidebars instead of seeing just one.
VISIT https://wordpress.org/plugins/advanced-widgets/
Español:
Un maravilloso plugin para poder crear fácilmente muchos sidebars. Estos sidebars luego los podremos seleccionar en la creacián de un post / page / custom post type / category / taxonomy. Podremos darle un orden, y seleccionar varios a la vez. 
Se verán todos los sidebars activos.
VISITAR https://wordpress.org/plugins/advanced-widgets/

Multiple Sidebars

A wonderful plugin to easily create many custom sidebars. These sidebars can then select in the creation of a post / page / custom post type / categor …

Per Page Widgets vs Multiple Sidebars