Greasy Fork is available in English.
show an entry page's preview in inline frame on the Tumblr Mega Editor page when the mouse cursor is on.
To make this script enabled, setting a browser option to allow to show mixed-content is required after install this script.
For instance in FireFox, please set false to the (about:config -> security.mixed_content.block_active_content) option.
In Chrome, please go to your tumblr mega-editor page and mouseover the post, and then click the shield icon at the right end of the address bar and click "Load unsafe scripts" button.
PLEASE DO IT AT YOUR OWN RISK