JavaScript Programmers Can't Stand on top
The catch of an innocent identifier as global variable

On the top
Please, before you throw anything at me, take a look at the code below.
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You can't stand on top

Testing "top" as global variable
You can open Testing "top" as Global Variable Identifier.
Chrome: ErrorUncaught TypeError: Cannot assign to read only property 'top' of object '#<Window>' ...
Firefox: Uncaught TypeError: setting getter-only property "top" <anonymous> ...
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Standing on bottom is OK

Testing "bottom" as global variable
You can open Testing "bottom" as Global Variable Identifier.
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Notes
You may use "top" to name a local variable (declared inside a function), but not to name a global variable (declared outside a function).
But its "inferior" friend, "bottom" you can use as local and as global variable name.
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This article was made using
- Chrome version 85.0
- Firefox version 79.0
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I had a bad time in the past because Chrome (old version)
- allowed me to declare "top" as global variable
- silently rejected the assignment to global variable "top"
A bad time...