diff --git a/src/output.jl b/src/output.jl
index fd37c10e..8b3527c7 100644
--- a/src/output.jl
+++ b/src/output.jl
@@ -250,7 +250,7 @@ function showjuno(io::IO, m, plt)
 end
 
 function _showjuno(io::IO, m::MIME"image/svg+xml", plt)
-  if Symbol(plt.attr[:html_output_format]) ≠ :svg
+  if !(plt.attr[:html_output_format] in (:auto, :svg))
     throw(MethodError(show, (typeof(m), typeof(plt))))
   else
     _show(io, m, plt)