humanmade/WPThumb — pull request #86 by joehoyle (2013-10-18 15:50:53+00:00)
Title: Interfering with normal image insertion 

With the plugin active, a /cache/ folder is being created in the wp-content/uploads/ folder, and it is interfering with the uploading of images in posts and pages. Basically when you upload an image into a post, the name is being changed and its url also modified to point to the version in the /cache/ folder, which shouldn't be the case.

The problem manifests itself when the image inserted into the editor is not the full size version but one of the other sizes WordPress generates.