Blank captions don't work

[luffer]

If you add a blank caption (space) to an image, it ignores the caption and doesn't frame the image.

What should happen is that a caption frame be added to the image with a blank space as the caption. Without this behaviour, there is no way to get a caption frame around images without adding a caption.

NOTE: This was tested using the default theme with no plugins.

I'd assume this is by design. You can't caption something without an actual caption. If you just want a specific design for your image, you should go with a custom image class and style it with CSS.

Completely agree with @greenshady, Also there is a filter - img_caption_shortcode, which can be used to enforce the caption div even if the caption field is empty.

I would agree as well.