Get extents of multiple brushed regions


I’m working with R, shiny and plotly. I noticed that multiple areas can be brushed by holding down the alt-key. However, only the last area that was brushed is given by event_data("plotly_brushed"). Is there some way to access the extents of all areas that are shown in the plot as being brushed?

Thanks for any reply.

plotly_example("shiny", "event_data")

See screenshot below. I selected from left to right. Selected points are correctly reported, but the third grey box states the brushing going from 20.03 to 24.97, i.e. the right-most, last brushing area.