Hello lazarus project!

this error shown in Linux 32bit up-to-date SVN with GTK2:

ERROR in LCL: TGtkDeviceContext.SetWidget: Unable to realize GdkWindow Creating gdb catchable error:
$086ECC48 RAISEGDBEXCEPTION, line 1497 of /usr/local/share/lazarus/lcl/lclproc.pas $08819C33 RAISEUNABLETOREALIZE, line 234 of /usr/local/share/lazarus/lcl/interfaces/gtk2//usr/local/share/lazarus/lcl/interfaces/gtk/gtkdevicecontext.inc $08819BA0 TGTKDEVICECONTEXT__SETWIDGET, line 277 of /usr/local/share/lazarus/lcl/interfaces/gtk2//usr/local/share/lazarus/lcl/interfaces/gtk/gtkdevicecontext.inc $088264C6 TGTKWIDGETSET__CREATEDCFORWIDGET, line 4487 of /usr/local/share/lazarus/lcl/interfaces/gtk2//usr/local/share/lazarus/lcl/interfaces/gtk/gtkwidgetset.inc $0882FF50 TGTKWIDGETSET__GETDC, line 5011 of /usr/local/share/lazarus/lcl/interfaces/gtk2//usr/local/share/lazarus/lcl/interfaces/gtk/gtkwinapi.inc $0873220F GETDC, line 356 of /usr/local/share/lazarus/lcl/./include/winapi.inc $087747CC TWINCONTROL__GETDEVICECONTEXT, line 7293 of /usr/local/share/lazarus/lcl/./include/wincontrol.inc $087649D2 TCONTROLCANVAS__CREATEHANDLE, line 90 of /usr/local/share/lazarus/lcl/./include/controlcanvas.inc $087454B6 TCANVAS__REQUIREDSTATE, line 1564 of /usr/local/share/lazarus/lcl/./include/canvas.inc $08742AC3 TCANVAS__SETPIXEL, line 111 of /usr/local/share/lazarus/lcl/./include/canvas.inc

This is shown, when component wants to access:

Canvas.Pixels[xR, yR] := MColor;

What could be a reason?

Thanks.