IE6/Win: ignored margins

Note: This paper remains in very early draft form.

Characterization of the bug in IE6

Suppose we have

1. a hasLayout container (necessary)
2. with padding-top or border-top (axiom)
3. containing a child (necessary)
4. AP element (axiom) that is
5. immediately followed by (necessary) an
6. in-flow (necessary)
7. hasLayout (necessary)
8. sibling (necessary) X. Then, unless the AP element is the last in
9. a consecutive sequence of (necessary)
10. any number of (exhaustive)
11. arbitrarily ordered (exhaustive)
12. floated and AP (necessary)
13. siblings (necessary) of which
14. at least one is a float (necessary),

the top margin of X is treated as 0.

Example 1 gives one of the most basic test cases, in which a hasLayout container holds an AP element followed by a hasLayout element. This could be simplified further by just making these latter elements direct children of body.

Uninvestigated questions:

• A whole different set of bugs arises when the hasLayout container does not have padding-top or border-top (so permitting margin-collapsing of its first in-flow child’s margin-top).

Notes

None.

Example 1. hasLayout non-RP container with AP child and hasLayout top-margined child. Margin is ignored.

Example 2. hasLayout RP container with AP child and hasLayout top-margined child. Margin is ignored.

Example 3. non-hasLayout container with AP child and hasLayout top-margined child. OK.

Example 4. hasLayout container with AP child and non-hasLayout top-margined child. OK.

Example 5. dimensioned container with AP child and hasLayout top-margined child. Margin is ignored.

Example 6. floated container with AP child and hasLayout top-margined child. Margin is ignored.

Example 7. AP container with AP child and hasLayout top-margined child. Margin is ignored.

Example 8. I-B container with AP child and hasLayout top-margined child. Margin is ignored.

Example 9. hasLayout container with AP child and dimensioned top-margined child. Margin is ignored.

Example 10. hasLayout container with AP child and floated top-margined child. OK.

Example 11. hasLayout container with AP child and AP top-margined child. OK.

Example 12. hasLayout container with AP child and I-B top-margined child. Margin is ignored.

Example 100. hasLayout grandparent with non-hasLayout parent with AP child and hasLayout top-margined child. OK.

Example 1. hasLayout non-RP container with AP child and hasLayout top-margined child. OK.