Unicode errors in simple program

[RandomUser14]

I have a program that accepts a string of normal characters and keeps adding unicode invisible characters until a certain condition is met. 

Local $WorkingValue = [DEFINED BY SCRIPT]
Local $InvisibleCharacter = "[IMAGINE INVISIBLE CHARACTER HERE]"
Local $Output = _StringInsert($Output, $InvisibleCharacter, $WorkingValue)
ClipPut($Output)

Keep in mind that this could add hundreds of characters, and this problem is only encountered when it does so. 

I've tried saving the script in UTF 8 with BOM and UTF 16 Little Endian, no dice. How do I fix this?

[RandomUser14]

Sorry for double posting I couldn't find an edit button. The problem is the text is filled with THIS character "‭‭󠁾󠁾‭󠁾‭‭󠁾‭󠁾󠁾�" instead of the invisible one picture only when it pastes a lot of it.

The character is a unicode tag glide U+E007E 

[jchd]

Post short reproducer script.