> ALLOW OVERWRITING CODE PROTECTED FLASH (but never can read it!)

I am not familiar with the new F87x code protection options.

BUT...

Allowing overwriting of flash is never a good idea.  Imagine that
I can guess what code generation tools you use, for whatever reason - and
be it simply a compromising "divide by zero" debug message with typo (been
there, seen that).  Imagine that I can guess the startup code of your product,
and you let me further program it.

I BET that I would find a pattern to burn 1's to 0's in a way that the
(known) startup code is modified into a 1st class security hole.

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