Content spilling out of a floated child does not make parent container styled with overflow: auto generate vertical scrollbar in Internet Explorer 8 beta 2 and in Opera 9.62

1st child, with yellow background-color and floated right: it has the declarations
height: 100px;
width: 300px;

and thanks to a lot of text, its content will overflow such dimensions and such content will spill outside its boundaries. Now, what should happen is the #parent-container should provide a vertical scrollbar because the content of one of its children is spilling outside and because #parent-container has the declaration overflow: auto. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling. More filling.

2nd child, with green background-color, non-floated

Expected results: the red-bordered box should generate, should render a vertical scrollbar to allow the user to reach, to access the overflowed content. The yellow background box has a lot of text and the red bordered block has the declaration overflow: auto.

Actual results in Internet Explorer 8 beta 2, Opera 7.11, Opera 8.53 and Opera 9.62: the red-bordered box does not render a vertical scrollbar

Internet Explorer 7, Firefox 1.5, Firefox 2.0.0.4, Firefox 3.0.4, Safari 3.2, Safari 4.0, Konqueror 3.5.10, Konqueror 4.1.1, NS 7.2, Seamonkey 2.x, K-meleon 1.x, Galeon 2.0.4, Epiphany 2.22 all pass this test.

This bug has been reported at connect's IE beta feedback as bug 382351.

This bug has been reported at Opera Bug Tracking System as bug DSK-239664

Update: this bug has been FIXED in Internet Explorer 8 Partner pre-RC1 build 6001.18343 released on December 11th 2008. Otherwise, Internet Explorer 8 Partner pre-RC1 build 6001.18343 PASSES this specific and particular testcase.

Update: this bug has been FIXED in Opera 11.10 build 2092 released on April 12th 2011.

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