This is related to earlier posts on rescaling images after posting, but I'd like to propose a feature similar to Wikipedia.
There clicking on an image that appears in an article links to display of a larger version of the image (and supplementary information) if one is available.
In some cases Questions and Answers on Math.SE benefit from fairly detailed images, but displaying them at full size (by default) could or would break up the flow of text for Readers.
Optional use of "thumbnailed" sizes
s appended to the filename in the image links embedded in posts allows detailed images to be uploaded but shown at reduced scale in the context of their posts.
Perhaps StackExchange already allows enough "embedded" HTML to implement something of this kind, but it would be a kindness IMHO to automate the function where the thumbnail feature has been used to give a reduced display size in a post.
Added: I considered posting this to Meta.SE, but since my motivation is really for graphics as I use them here, I thought Meta.Math.SE was at least a good place to get feedback.