Calendar view running out of space when images used

I’ve just posted a new event with an image and some descriptive text. Sadly, when viewing it on the calendar (old style), the drop-down box is too small to show the image, the description and the venue/time and “More information” link. (The bottom information just isn’t displayed and there’s no way of accessing it.)

Can this box be extended to match the content, please?

Thank you