Cannot assign to read only property 'length' of object '[object Array]' code example

Example 1: Cannot assign to read only property '0' of object '[object Array]'

array = array.slice().sort((a, b) => b.stats.speed - a.stats.speed)

Example 2: Cannot assign to read only property 'value' of object '[object Object] js

elementReadOnly = {...elementReadOnly, fieldModified: value};