Actually I use FireFox usually, and the problem is found a couple of month ago.
So I downloaded all the image for blogging purpose, and it’s too tough to posting things based on internet collected content.
I like locally copied image when I post blog stuff, because the linked image file can be erased easily.
Even though this is little bit uncomfortable than copy and paste, I found the way to clear this problem.
I recommend you to use one of the below plug-ins.
One thing uncomfortable comparing with copy-and-paste(copy image to clipboard on browser and paste with CTRL+V on livewriter) is you need to follow the following procedures:
1) Copy Image to clipboard on browser
2) Click insert menu on livewriter and select Clipboard Live or Clipboard Capture