Problems with Plots.jl figure


I am really having trouble getting a heatmap figure out. I would be grateful for any help regarding this. I am enclosing a mwe for it.

p3=Plots.heatmap(x,y,z,colorbar_tickfontfamily="Computer Modern",
colorbar_ticks=( [-π:π:π],string.([L"-\pi",0,L"\pi"])),colorbar_tickfontsize=20,size=s1,yticks=false,title="(c)")

Plots.plot(p2,p1,p3,xticks=(-40:40:40),xtickfont=20,layout = @layout([a{0.29w} b{0.29w} c{0.4w}]))

So it has 3 subfigures with a colorbar which has custom ticks. I am using Plots with pyplot() backend for this. Now the problem is with saving the figure. . If I try to save this as a pdf I fall into this problem(White lines in saved pdf-file · Issue #1345 · JuliaPlots/Plots.jl · GitHub) with white lines on the pdf file after saving. I still need the custom ticks labels in the colorbar hence cant move to gr() backend either.

If anyone can point me to the direction of making custom colorbar ticks via pgfplotsx() backend or any other backend, that will be pretty cool as well. Or else one has to actually move from Plots to some other package.