Tring to remove first character from a string if it's a particular emoji

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How LR handles Unicode strings in Lua isn't documented anywhere I know of (except on this forum).

Lua strings are sequences of 8-bit bytes, and Lua itself doesn't understand any Unicode encodings. If you write the following in a .lua source file and save the file encoded as UTF-8:

the source file contains four bytes between the open and close quotes. (The Unicode Red Textbook character is encoded in UTF-8 as four bytes.) Lua reads it as a four-byte string "\240\159\147\149". For example:

Lua doesn't provide any built-in operations for manipulating strings as sequences of Unicode characters, though there are open-source modules that provide UTF-8 operations on Lua strings.

LR generally treats Lua strings as containing UTF-8 encodings, so when LR displays a Lua string in its UI controls, it will interpret the string as UTF-8. (The screenshot above is from my debugging toolkit, which uses LrView controls.)

Finally, to remove the Unicode Red Texbook character from the beginning of a string, you could write: