Code macro has solid border and unnecessary horizontal scroll bar

I'm using the Code Macro (2.1.4) on Confluence 5.4.4 - when I use the Code Macro plugging it has a solid border and a completely unnecessary horizontal scroll bar (screenshot attached) - this is just a blank page with a Code Macro.

I've looked through all the settings and can't seem to find anything - any ideas?

I want the blocks to look how they do in Atlassians documentation with the dashed border and no horizontal scroll bar, such as on this page:
https://confluence.atlassian.com/display/JIRA/Advanced+Searching+Functions#AdvancedSearchingFunctions-endOfYear()