Image Size pop up menu missing in Mac Mail

Hi all,

I've just noticed a very frustrating problem with my mac mail which seems to have started recently, for no apparent reason. I have made no updates to my mac mail at all.

Basically when I attach and image to a new email, there used to be a pop up menu appear in the bottom right of the window where you can select the size of the image - small, medium, large or actual size.

This has randomly disappeared!

I cannot find any settings in the preferences for it to reappear. I have made no changes that would have caused this - at least not knowingly.

Any ideas as to how I can get the image size pop up menu to reappear when I am attaching images to a new email?