Hi @Adam
You are using Plotlys on_selection. I’ve never seen that used in a Panel context. If you would expect that to work please add a Feature Request to our Github.
What you can currently use is described in Plotly — Panel 0.12.6 documentation (holoviz.org).
There is an example using click_data here How to capture the click event on Plotly plot with Panel? - Panel - HoloViz Discourse
If you need a concrete example for your use case, please post a minimum reproducible example we can start from. Thanks.