Campaign Content Editor: Keep Image Width on Mobile

Images in rows whose columns do not stack on small screens are scaled down proportionally with the column. A new option in the image style settings marks an individual image to keep its configured width below a responsive breakpoint, while all other images continue to scale as before. The option is set per breakpoint. Use case: A 64 pixel avatar next to a text column stays legible on a phone instead of shrinking to roughly half its size.