This is a page from the Cascading Style Sheets Working Group Blog. Some other places to find information are the “current work” page, the www-style mailing list, the Future of CSS syndicator, and the issue list on Github.
Do you want to know how the CSS WG works? Fantasai has written about:csswg, An Inside View of the CSS Working Group at W3C.
background-break and border-break into box-break; fantasai to draft proposal into Editor’s Draft for discussion.min() and max() functions to calc(); min() and max() may also appear as standalone functions, their contents parsed as if wrapped in calc().