css - 位置 :fixed will trigger the display:block?

Question

我测试过，在 chrome 或 firefox 上运行时，除了 ie，
position:fixed 会触发 display:block 吗？
这是测试 html:http://sking7.github.com/fix.html
代码会提醒两次，第一次是显示，第二次是 document.compatMode
这是为什么？
w3c 已经这么说了？

Answer 1

好吧，我找到了w3 specifications for this :

9.7 Relationships between 'display', 'position', and 'float'

The three properties that affect box generation and layout — 'display', 'position', and 'float' — interact as follows:

1. If 'display' has the value 'none', then 'position' and 'float' do not apply. In this case, the element generates no box.
2. Otherwise, if 'position' has the value 'absolute' or 'fixed', the box is absolutely positioned, the computed value of 'float' is 'none', and display is set according to the table below. The position of the box will be determined by the 'top', 'right', 'bottom' and 'left' properties and the box's containing block.
3. Otherwise, if 'float' has a value other than 'none', the box is floated and 'display' is set according to the table below.
4. Otherwise, if the element is the root element, 'display' is set according to the table below, except that it is undefined in CSS 2.1 whether a specified value of 'list-item' becomes a computed value of 'block' or 'list-item'.
5. Otherwise, the remaining 'display' property values apply as specified.

Specified value                                     Computed value

inline-table                                        table

*inline*, table-row-group, table-column, 
table-column-group, table-header-group, 
table-footer-group, table-row, table-cell, 
table-caption, inline-block                         *block*

others                                              same as specified