Board Thread:Support Requests - Designing Your Wiki/@comment-24203080-20170302072944/@comment-25390652-20170302102217

As I know, the image takes all given width by default, and you can't set it by using parameters. The image in the example you linked is already as wide as the infobox. However, you can: it would affect all templates though, if you only want to affect only a few, then you need to... this way, infobox with theme-source="ImgWidth" will give you proper size when you use
 * Set maximum width or padding (or both):
 * change the width of certain themed infoboxes. I.e. replace .pi-image-thumbnail with .pi-theme-City .pi-image-thumbnail
 * use javascript based on the usage of theme-source attribute

or

, for example

I haven't tested it, but should work, I think.

EDIT: Tested, everything works now.