I'm trying to get plotly to work as a backend to Plots.jl but have no luck with either Julia 0.7, Julia 1.01 or Julia 1.10.
With Julia 0.7, I get no error messages but no plots display (blank canvas).
With both Julia 1.01 and 1.10, I get the following error message:
"only png or svg allowed. got: :html"
I'm using this in a Jupyter notebook (Anaconda install) in google chrome browser.
I've found the same problem using Windows 10, Julia 1.1.0, Plots 0.24.0, PlotlyJS 0.12.3 and IJulia 1.18.1 (Jupyter 5.7.0)

Code example:
using Plots
plotlyjs()
showlibrary(:Plots)
Also WebIO v0.8.1, this is related to https://github.com/sglyon/PlotlyJS.jl/issues/278
See #1985. Rolling Plots back to version 0.23.1 works. (I'm using JupyterLab and Julia 1.1)
With #2125 this should now work for Plotly, not yet for PlotlyJS though.
Thanks, when will this be updated in a release? I'm running Plots 0.25.3 and still getting this error. (I don't know on what schedule the fixes on github enter the release versions)
It's included in Plots 0.26.1, which will be released soon (as soon as https://github.com/JuliaRegistries/General/pull/2547 gets merged).
Fixed in #2131
Still not working, not sure what version I'm at, hopefully latest version, as it's just installed.
Most helpful comment
I've found the same problem using Windows 10, Julia 1.1.0, Plots 0.24.0, PlotlyJS 0.12.3 and IJulia 1.18.1 (Jupyter 5.7.0)
Code example: