The same thing happens with my vertical panel on the left edge of the screen: when it is hidden, three pixels toward the bottom of the panel are missing, or more precisely, drawn black. See attached screenshot. (I only changed the colour of the panel to bright green to make it more obvious in the picture.)
Here's another thing I noticed: when I opened the Xfce Settings Manager, entered the Appearance screen and changed the font hinting setting, my autohidden left panel lost more pixels. It looks like the bottom part of the panel starting from the already-black pixels changed to black. I'm attaching another screenshot. ** Attachment added: "The bottom-left corner of my screen with vertical panel in autohide mode" https://bugs.launchpad.net/ubuntu/+source/xfce4-panel/+bug/880504/+attachment/2598088/+files/panel-bug-b.png -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/880504 Title: Pixel bugs in xfce panel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xfce4-panel/+bug/880504/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs