This continues bug 41847. If you change the font size with the text zoom tool, Mozilla 1.0RC1 (WinNT4) does not change change the dimensions and positions of fixed positioned elements, if these dimensions are given in 'em', until you reach a certain threshold. That threshold changes according to no apparent rule. Mozilla recalculates the DIV's dimensions immediately, if you change the window size, even if that change is only one pixel, or if you reload the page. em's for elements with position:absolute are calculated correctly, by the way. See the test case at http://xren.sourceforge.net/_moztestcase/em0.shtml, the description there might be better than that above. Note that I know about bug 51578 which might be related in some way. However, I don't think these are the same.

The threshold is the point at which the <pre> text gets wide enough to require a horizontal scrollbar. At that point the viewport frame reflows and the fixed-position divs are reflowed.... I'm pretty sure this is in fact a duplicate of bug 51578 -- the fix is the same (to reflow the viewport instead of the root frame). Oh, this happens on Linux too. :)

The fix for bug 51578 fixes this.... *** This bug has been marked as a duplicate of 51578 ***

Changing QA Contact

verified dup -