Cannot add property 0, object is not extensible

code:js

foo = []

Object.freeze(foo)

foo.push(1)

// Uncaught TypeError: Cannot add property 0, object is not extensible

Happens when trying to push against a frozen Array

Specific Occurrence Situations

https://gyazo.com/3bf53b670627bf0743ac495b6d3137d6

So why was it frozen?

The selected element is being put into ReactN and then frozen when it is taken out. Kindly designed to prevent inadvertent destructive updates and a nasty bug.

When grouping the selected ones, this is what was written, which is wrong

code:ts

const group = new GroupItem();

group.items = g.selected_items;

This will cause the new group to have a reference to the frozen object itself, and then when you try to add to that group, you will get the above error.

code:ts

group.items = ...g.selected_items;

This is what I should have done.

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