Joseph Fusco

Disables responsive images introduced in 4.4. This plugin is only meant to be a temporary solution to fixing conflicts with certain plugins and themes. Responsive images drive the web forward. 
Credit for solution goes to Birgir Erlendsson.

Disable Responsive Images

Disables responsive images introduced in 4.4.

PStevenson

In short, this plugin modifies “the_content()” and the post thumbnail function by re-rendering the images with use of the SRCSET attribute. Other plugins do this for templated images, but not in the content region itself. This plugin will automatically work with any previously uploaded images as well.

Post Script Responsive Images

SRCSET responsive images on wordpress for content images.

Disable Responsive Images vs Post Script Responsive Images