Description
The problem is that the horizontal legend overlaps the x-axis title. It occurs if the legend is positioned below (rather than to the right of) the plot area using layout = {legend: {"orientation": "h"}};
. It aggravates in combination with multiline x-axis titles (using <br>
tags).
Currently there's no way to control the spacing between the legend and the plotting area. Everything is auto-scaled, it is useless to set the bottom margin (layout = {margin: {"b": ...}};
) in this case because it refers to the space below the legend. The only way to make the whole x-axis title visible is to increase the height of the whole plot until the autoscaling sufficiently spreads the legend and the plotting area apart.
I try to illustrate the problem with the following 3 images which differ only in frame height:
Here is the above plot hosted on plot.ly.