Re: [csswg-drafts] [css-tables] Collapsed table borders don't follow sticky rows/cells when they stick (#3136)

I've ran into another place where table painting of collapsed borders does not work: fragmentation.

When table is fragmented, headers/footers might be repeated on every page when table is printed.
This means that headers will share borders with multiple different tbody rows.

I call these cases "fluid grid" cases. "Table paints collapsed borders" assumes that grid is static: cell location is fixed, and table parts do not generate new stacking contexts. But, we have cells that violate these assumptions:
- position:fixed cells generate new stacking context, and change location
- fragmentation can change cell's location, and neighbor cells.
- various css properties can generate new stacking contexts.

I think there is a place in the spec for both types of painting. Painting borders by a cell cannot handle some cases:
- intersection painting of non-adjacent cell borders, see issue #6039
- painting of column/row borders when cells do not exist. (FF's always done this, TablesNG does it now too).

I think that following would be the most powerful solution:
- paint all collapsed borders by table
- fluid cells also paint their own half-borders, like the spec specifies today.

I would like to understand how "self-painting borders" handle intersections.


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Received on Wednesday, 21 April 2021 06:59:18 UTC