DisplayFusion is causing http://store.steampowered.com/about/ to ignore the resolution of the secondary monitor when it is maximised if the secondary monitor is a lower resolution (I do not know what happens in the reverse scenario, where the secondary monitor is a higher resolution).
In my case, the primary monitor (left) uses 1920x1200 as its resolution while the secondary monitor (right, bottom-aligned) uses 1680x1050 as its resolution. When maximising Steam on the secondary monitor with a DisplayFusion taskbar active Steam will maximise as though it was attempting to fill the 1920x1200 monitor and thus has a section of the right/bottom edges of the application cut-off. This issue occurs with other Steam windows as well (such as the Friends list); it appears that all of these windows belong to the one Steam.exe (they don't spawn processes of their own, if that's useful).
The only workarounds I have discovered are to not maximise Steam on the secondary monitor (smaller) or closing DisplayFusion to disable the taskbar.
Note: Using a third-party image host because attaching the 560KiB file (despite the 5MB limit) gave me the error "PHP Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 1920 bytes) in C:\Web\BinaryFortress\Root\Forum\Sources\Subs-Graphics.php on line 389". Good thing I wrote my post in notepad or I'd have lost it a few times.
Scroll right to see the impact, if your resolution is low enough to cause image scrolling.
Just a quick note about the image attachments, next time just upload the 4 images separately and it should be ok. Combining the 4 images into 1 large image makes it hard to see them all.
This looks like a Steam issue (it wouldn't be the first one) but I'll see what I can do. Thanks!
I have good news and bad news. The good news is that I was able to reproduce this issue on my test machine. The bad news is that it is a Steam issue. Even if I exit DisplayFusion and dock a different application to the screen edge (like Winamp or Google Desktop Sidebar) Steam still presents the same issues. Hopefully the folks at Valve will realize this issue exists and fix it.
Thanks for looking into the bug for me, I didn't have any other docking applications so I hadn't considered testing for that. I took your advice on the image splitting (not really sure why I didn't do that before) and reposted the bug report on the Steam forums http://forums.steampowered.com/forums/showthread.php?p=15113832 =)
Hopefully the folks at Valve will realize this issue exists and fix it.
