When saving a layout and opening a new session, or when reapplying a layout immediately after saving it, the dividing lines between the tabs in the layout are offset.
Steps to reproduce
Change your layout by dragging the dividing lines between the tabs around.
Save the layout (Layouts > Save Current Layout....)
Close the session and reopen Katana, or immediately reapply the layout under Layouts > (Name of your layout). Result: The layout is offset.