image rescaled when switchin between tabs

[zuban]

Binary package hint: firefox-3.0

when web page on some site is zoomed using Menu -> View -> Zoom -> Zoom In/Out, than displaying an image url on such site, the image is initially rescaled too. When one clicks on the image with Zoom cursor, the zoom switchtes between "1:1" and "Fit to page" and initial zoom cannot be obtained again. When one switches between tabs and back to the image, image is zoomed again in the initial zoom selected in menu.
Firefox version: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.7) Gecko/2009030422 Ubuntu/8.04 (hardy) Firefox/3.0.7

ProblemType: Bug
Architecture: i386
Date: Sun May 10 11:11:57 2009
DistroRelease: Ubuntu 8.04
Package: firefox-3.0 3.0.7+nobinonly-0ubuntu0.8.04.1
PackageArchitecture: i386
ProcEnviron:
 LANGUAGE=en_US:en
 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: firefox-3.0
Uname: Linux 2.6.24-19-generic i686