Squaring an area incorrectly deletes a node from the corner

[CorruptComputer]

URL

n/a

How to reproduce the issue?

1. Add a slightly unsquare area
2. Square it in the right-click menu
3. One of your corners may get deleted

Screenshot(s) or anything else?

Video of issue: https://youtu.be/eYGU4GIWMyw

changes.osc file: changes.txt

• renamed from .osc to .txt because of GitHub file upload rules

Which iD Editor versions do you see the issue on?

Released version at openstreetmap.org/edit (2.21.0 at the time of reporting)

Which browsers are you seeing this problem on?

Vivaldi (not an option in the browsers list, but is Chromium based)