As requested, here's a separate topic for an alternative version of OneBar, in which locked tabs are shown as favicon-only small-size tabs: the lock indicator and the page title are hidden.
For screenshots in OS's other than XP, see http://forum.maxthon.com/thread-8774-1-1.html
The address bar unfolds when activated
If you want to move/drag the window, use the spacer between the menu and back buttons
New version (April 15, 22:30 UTC/GMT):
Fixed the maximum width of tabs
Removed Refresh button for more horizontal space: use F5, or Shift+F5 to refresh all tabs, and Ctrl+F5 to force refresh
Removed Favorites button (when Favorites bar off): just use default keyboard shortcut Ctrl+B, or set a more ergonomic shortcut, like Alt+A
New version (April 21, 01:00 UTC/GMT):
Fixed private mode indicator position
Turns out I did like the Favorites button: reintroduced
Width of navigation buttons slightly altered for more horizontal space.
New version (April 21, 15:30 UTC/GMT):
Gained another 2 (!) pixels vertically, hurray!
Dirty fix for navigation buttons not showing up in W8, possibly Vista/W7 (there's something wrong with it when the opacity is <1 since Maxthon v4.4.0.2000). Thx2 大笨狗
New version (April 29, 8:45 UTC/GMT):
New Tab button now sticks to the right of the tabs instead of jumping all the way to the right
"Overshoot" when clicking on (expanding) the address bar is less ugly
Made resizing of window easier (hit-margin expanded)
New version (May 10, 12:21 UTC/GMT):
New Tab button fix of previous version caused Maxthon to lose the last session tab and all locked tabs upon restart. It's a real strange thing for such a small change. I removed the change, so you can use the skin safely again.
New version (June 5, 19:00 UTC/GMT):
Little fix needed for Maxthon v4.4.1.1000
Download: https://db.tt/cE0J1Xj4
For those who want to adjust the skin to their own preferences, the maximum tab width had to be hard-coded (to 232px), so the skin3.ini variable doesn't work anymore, change in skin.css.
Tip: to save some horizontal space, you might want to edit Maxthon\Language\en.ini to make the Reader Mode button smaller. Change it into something likeReaderMode.Available=Reador you could even make it 'button-only' by putting only a space there (although the tooltip is gonna be blank then, too).