What is the best way to fix it (the border/margin)?
In general, I’d like some margin around photos inserted via the Wordpress-editor. I’ve tested numerous ways of doing it, but what is considered to be ‘best practice’ ?
I would carefully consider the thumbnail sizes and rewrite the code to make everything responsive. But if time is a factor, adding the extra 10px to the figure is fine and we haven’t been able to come up with anything more suitable (yet).