Subplot problems with histograms

Hi Guys trying out the PoltlyJS package. I wanted to plot the classic iris data set. I was trying to build my own pairplot. However, plotlyJS gives some strange behavior. When I subplot the histogram it no longer overlays and the binning appears to change as the height of the histogram changes.

using PlotlyJS
using CSV
using DataFrames

col_names = ["SepalLength", "SepalWidth", "PetalLength", "PetalWidth", "Class"]
iris ="iris.csv"; header = col_names, normalizenames = true)
iris = groupby(iris, :Class)

gp_1 = iris[1]
gp_2 = iris[2][1,5]
gp_3 = iris[3][1,5]

function histo(df::GroupedDataFrame, i::Int)
    data = typeof(histogram())[]

    for k in 1:length(df)
        x = df[k][!,i]

        fields = Dict{Symbol,Any}(
            :type => "histogram",
            :x => x,
            :opacity => 0.5,
            :nbinsx => 10

        trace = GenericTrace("histogram", fields)
        push!(data, trace )
    return data

function scatt(df::GroupedDataFrame, i::Int, j::Int)
    data = typeof(scatter())[]
    col = i
    row = j

    for k in 1:length(df)
        y = df[k][!,i]
        x = df[k][!,j]
        trace = scatter(x=x, y=y; mode="markers")
        push!(data, trace)
    return data

layout = Layout(barmode="overlay")
p1 = plot(histo(iris, 1), layout )
p2 = plot(scatt(iris,2,1))

[p1 p2]

If just plot the histogram you get

If you stack subplot it via [p1 p2] the you get

Any help would be appriciated.