WordPress editor supports inserting images from the clipboard, but the pictures are bad Data:URL type.
This plugin converts image files in PNG format on a server.
Insert a copy of the windows screen in the post or page – a good example for the use of this plugin.
It is very comfortable.
<h3>Arbitrary section 1</h3>

Save Data:URL images

WordPress editor supports inserting images from the clipboard, but the pictures are bad Data:URL type.

kr4ft3r

Multisite support added in v0.6!
Notice: this plugin will not have further major updates. If interested in new features, please upgrade into this compatible replacement: https://wit.rs/wp-plugins/wit-custom-output 
After uninstalling the WPCHTMLP and installing WIT Custom Output, your old custom pages will still work, but with better interface, more features and regular updates.
WP Custom HTML Pages plugin has two functionalities:
1 – Create a custom HTML document output at a custom permalink address, completely bypassing WordPress templating. This is useful in cases when you just want to output some HTML without uploading the page to the server.
2 – Create a shortcode which outputs your custom HTML.

WP Custom HTML Page

Display full custom HTML on custom permalink address, or put it inside content as a shortcode.

Save Data:URL images vs WP Custom HTML Page