Python 3.4.4 GUI shell 'IDLE' has a strange drawing glitch that could be related to scrollbars

0.4.12-RC-50-geb1a43d gcc dbg lin is affected.

Reproduction steps

• install Python 3.4.4 from rapps
• Run its graphical shell from startmenu, It's called 'IDLE'
• select 'Options' from menubar and select 'Configure IDLE'
• select the last register tab 'Extensions' from this dialog

Observed result
0.4.12-RC-50-geb1a43d__python3_4_4_drawingGlitch.png
The dlg has some strange drawing glitch above the 'apply' button, that shouldn't be there and does not vanish when I drag the dlg offscreen and back.
Although the dlg shows no scrollbars on ros, I still think that glitch is related to scrollbars drawing, because there actually should 2 two scrollbars visible.
0.4.12-RC-50-geb1a43d__python3_4_4_drawingGlitch.log is most likely useless, because nothing gets logged when opening the dlg.

Expected result
2k3sp2_python3_4_4_ok.png
2k3sp2 does not have that drawing glitch, (eventually because it draws the scrollbars correct?)