Product and version
FileMaker Pro Advanced 18.104.22.168 and FileMaker Pro Advanced 22.214.171.1245
OS and version
Base64Encode is not back compatible from FileMaker 16 on macOS.
The function adds an extra control character at the end of the base 64 string.
This doesn't create issues when using Base64Decode, but when using the function to calculate the basic auth of an API the extra character breaks the communication with the API.
Example: "Authorization: Basic " & Base64Encode( "myAPIkey" )
If it's completely superseded by Base64EncodeRFC, keeping it it's only interesting for back compatibility, and we lose it here
The extra character is only added on macOS, not on Windows, so the function is not consistent between OS
How to replicate
Length ( Base64Encode ( "test" ) )
returns 8 on FileMaker Pro 15
returns 9 on FileMaker Pro 16
Workaround (if any)
using Base64EncodeRFC ( 4648 ; "test" ) in FileMaker 16 is a workaround, but it means all existing scripts need to be changed