Source

beamer / beamerthemebars.sty

Diff from to

File beamerthemebars.sty

                                 % Frametitles
 \useframetitletemplate{%
   \vskip8pt
-  {\leftskip-\Geom@lmargin\advance\leftskip by0.3cm%
-   \rightskip-\Geom@rmargin plus1fil\advance\rightskip by0.3cm\leavevmode
+  {\leftskip-\beamer@leftmargin\advance\leftskip by0.3cm%
+   \rightskip-\beamer@rightmargin plus1fil\advance\rightskip by0.3cm\leavevmode
     \color{structure}
     \Large\insertframetitle\par}
   }