Thank you for pointing this. I would not doubt System.Security.Cryptography.RandomNumberGenerator is more secure, but I just want to draw your attention to this part: "...since the sequence of V4 GUIDs is pseudo-random; given full knowledge of the internal state, it is possible...
" While I am not really sure what "full knowledge" means in this case, I believe any attacker would have hard time retrieving it, given that they would only be able to collect a number of GUID's which are not guaranteed to be consecutive ones, and that makes RadChart secure enough. Nevertheless, I will make sure our developers are aware of your feedback.
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