Too many active WebGL contexts. Oldest context will be lost

**Describe the bug**
I'm in jupyterlab, exploring data, making plotlyjs.jl plots via Plots.jl. I see this warning in the console.

It's been [brought up as an issue against plotly.js](https://github.com/plotly/plotly.js/issues/337) but the developers there say that if you're re-drawing your graph multiple times, it's your own fault. After drawing a certain number of 3d figures, my jupyterlab tab crashes.

Is there a way to 'free' or 'clear' old webGL contexts when re-running a cell in a jupyterlab notebook? Would it make sense to add some logic to that effect in the `jupyterlab-plotly` labextension? Or is there a way to do it more simply on my end?

julia 1.6.0
[58dd65bb] Plotly v0.4.0
[a03496cd] PlotlyBase v0.5.3
[f0f68f2c] PlotlyJS v0.14.1
[91a5bcdd] Plots v1.13.1