[csswg-drafts] [css-multicol] box-decorations on boxes fragmented by a column-span (example 21 / figure 11) (#3575)

MatsPalmgren has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-multicol] box-decorations on boxes fragmented by a column-span (example 21 / figure 11) ==
https://drafts.csswg.org/css-multicol-1/#example-c0153f49

The red border in figure 11 looks wrong to me.  I think only the first fragment should have a block-start border and only the last fragment should have a block-end border.  Intermediary fragments should not have block-start/end borders. (All fragments should have inline-start/end borders though.)  I'm assuming [`box-decoration-break`](https://drafts.csswg.org/css-break-3/#break-decoration) has its initial value in this example.  `box-decoration-break:clone` should make all fragments have borders on all sides, as usual.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/3575 using your GitHub account