• please link to the spec section you're talking about, or at least the spec

  Somewhere here I would guess: https://www.w3.org/TR/css-align-3/

If I don't set height:0 to a last item in a flex column layout (while all items have flex-grow:0 except the last item that has flex-grow:1), then the last item's content expands beyond the edge of the layout.

This is confusing, and it was very time-consuming to figure out a solution of setting height: 0 (which doesn't make much sense considering the final height is not 0 but taking up whatever remaining space exists in the layout).

Reproduction, in Chrome:

reproduction.zip

• In element inspector, find the second element with class live-code-content.
• In the CSS style inspector, disable the height: 0px style.
• Notice the content of this element will overflow beyond the bottom edge of the layout.

Is this supposed to happen, or is there a bug?