unexpected javascript error in VBox linked to tooltip

[jgunstone]

trafficstars

ipywidgets version == 8.1.1

import ipywidgets as w

di = {
    "title": "title",
    "description": "Description ...",
    "tooltip": "tooltip ...",
}
w.VBox(**di)  # error

---

import ipywidgets as w

di = {
    "title": "title",
    "description": "Description ...",
    #"tooltip": "tooltip ...",
}
w.VBox(**di)  # instantiates normally

[jgunstone]

just double checked this in the newest version (8.1.5) and the error still persists

[fleming79]

The PR here #3921 resolves the problem.