"F%F%F%" Pattern: This pattern is less clear to me. It does not seem to align with standard hexadecimal notation or Bitcoin's varint encoding principles. Could someone shed light on the use and translation of "F%" in the early Bitcoin code or data formatting? Is this a custom encoding method, or does it have a specific application that is not widely documented?

specifier   Output   Example
...
F   Decimal floating point, uppercase   392.65