Creating the figure with selectedpoints does not register those points to the SelectedData

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Describe your context
Please provide us your environment, so we can easily reproduce the issue.

python version: 3.8.10

• replace the result of pip list | grep dash below

dash                 2.7.0
dash-core-components 2.0.0
dash-html-components 2.0.0
dash-renderer        Not installed
dash-table           5.0.0

• if frontend related, tell us your Browser, Version, and OS

  • OS: Windows 64-bit operating system
  • Browser: Chrome, (pretty sure its the same for every browser its an internal issue)
  • Version: 107.0.5304.88

Describe the bug

When creating a new figure with a preset selectedpoints,
The selectedData of the figure doesn't get updated and remains empty.

You can see this bug when running the example from https://dash.plotly.com/interactive-graphing Generic Crossfilter Recipe

First, we get an error when we select data because we check if selectedpoints_local exists, and then if the range exists,
the problem is that my guess is in the new versions of dash, selectedData property return a dictionary with {'points':[ ]},
which means it's not empty but the points list is.

if we check if the points list is empty before getting the range, we don't get an error.
But because the selectedData of the newly created figure is empty the second it's created the callback is called again with empty selectedData and removes all of our filters.

Expected behavior

I guess the expected behavior would be that the selectedData will be updated based on the data from the newly created figure
(which means the points, range, and maybe more stuff I don't know about)

Beginne mit dem Generic Crossfilter Recipe aus dem interaktiven Graphing-Beispiel und reproduziere den Callback mit einer Figure, die mit voreingestellten selectedpoints erstellt wurde. Untersuche, wie selectedData sowie dessen points und range behandelt werden, wenn die Figure erstellt wird. Erledigt ist dies, wenn selectedData die voreingestellte Auswahl widerspiegelt und der Callback die vorhandenen Filter nicht löscht.