There seems to be a bug when drawing a 1D histogram using “hbar” option. “hbar” allows to display bars horizontally, and therefore the “x” histogram’s axis is displayed on the y canvas’s axis. Histogram and canvas axis are reversed.
If on the canvas I click on the x axis (really the histogram y-axis) and select on the editor “log”, then the y-axis is set on the log axis! It is counter intuitive for someone using the GUI and mouse-and-click.