I have configured Image Renditions by enabling the BLOB caching on the web application in IIS and enabling publishing features on a Blog site. When I was inserting an image to the Body field when editing a Post (EditPost.aspx), the Pick Rendition button is DISABLED. The image I am trying to insert DOES reside within the same site collection as the Blog site. It works perfectly when adding an image to a Page Content area in a page, but not for EditPost.aspx and NewPost.aspx for Posts list. Also, when I go to Images library where stores all the images uploaded from my computer, when I click "..." on the image item, I can see Edit Rendition option, and it works fine. So I am guess rendition function is working, so now I am appending "?RenditionID=1" to the image url, and it's working, but not every end user will be able to do that even with training provided.
Strangely, in some other project I did the same things for a Blog site, and it worked. Really confusing and time consuming. Could you please look into this for me, thanks a lot.