How to remove black outline from Seurat's VlnPlot violin plot

Question

Using Seurat's VlnPlot, how can I remove the black outline around the violin plot?

For example, how can I change from the following graph with a (black) outline:

    VlnPlot(ilc2,
        features = "gene",
        split.by = "group", 
        cols = c("#198BFD", "#EC6464"),
        pt.size = 0) +
  geom_boxplot(width = 0.1) + theme(aspect.ratio = 1)

To a graph like the one below, which does not have an outline around the violin plot:

Answer 1

wish there was a more subtle answer, but this works. Place this previous to your VlnPlot

update_geom_defaults("violin", aes(linewidth = 0))

Answer 2

vln_df = data.frame(gene = ilc2_bs[["RNA"]]@data[ "gene", ],
                    group = ilc2$group)

ggplot(vln_df, aes(x = group, 
                   y = gene, fill = group)) + 
  geom_violin(aes(fill = group, 
                  color = gene),
              color = NA) +
  scale_fill_manual(values = c("#619CFF", "#F8766D")) +
  geom_boxplot(aes(fill = group),
               width = 0.1) + theme(aspect.ratio = 1)

Answer 3

I'd much prefer this as a comment, but anyway ...

 VlnPlot(ilc2,
        features = "gene",
        split.by = "group", 
        cols = c("#198BFD", "#EC6464"),
        color = NA, #  <--- HERE
        pt.size = 0) +
  geom_boxplot(width = 0.1) + theme(aspect.ratio = 1)

What I'm guessing is seurat is leveraging ggplot2 and thats how its done in ggplot2