Martin wrote (2020-12-31):

 MF> I have questions :)

 MF> [1]Is there any record anywhere of the reason(s) why these proposals
 MF> were rejected?

In some FRLs you find the reasons, but not in FSCs.

 MF> [2]Is a software developer permitted to implement any of these
 MF> rejected proposals in his/her software?

If you want to write a tosser, you have too implement some proposal that hasn't
made it to a standard (like FSC-0039). You can implement whatever proposals you
like, but most are just proposals and are rarely supported by any software.

Do we have a list of FSCs that are relevant?

 MF> [3]Am I correct in assuming that the FSP's are proposals awaiting
 MF> either acceptance or rejection by the FTSC?

The FTSC is practically dead, nothing will be accepted or rejected anymore.

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