Yes, I would also like to know exactly how the ”rebuild styles" function actually counts the number of styles available.

Does it count the actual styles in the styles folder, or does it come with a list of styles for a particular version of BIAB for which it then tries to match the available styles against? (if it comes with list is that list stored somewhere?).

I don’t find any logic in how it works! sometimes it just toggles count up or down 1-2 styles. Why is that? If it counts the styles, why is it counting differently sometimes).

I have also experienced that it may differ from time to time without having done any changes at all to the number of styles or the version of BIAB installed.

When installing an older version of BIAB, but with the styles intact and unchanged in the styles folder it also changes the number of styles after rebuild.

If I have ”my full set of styles” installed in the styles folder within BB, say after I have installed the 2024 BIAB I have 11131 styles.
If I then reinstall the 2023 BIAB then I only have 10270 styles after a rebuild.
If I then go back and install the 2024 BIAB I have again 11131 styles after a rebuild.
And so on it seems to change on each version of BIAB even if the number of styles in the styles folder have not changed.

Or does it mean that I have 861 styles (11131-10270) that only works in BIAB 2024 and not in 2023? but I have not seen any such notice.

It would be very interesting to know exactly how works.