Hi everyone,
Our 9-year old son recently bought an old typewriter at a yard sale and has gotten really interested in getting it cleaned up and working well.  I’ve been helping him a bit, and we figured out it’s a Smith-Corona 88 Secretarial from the mid-1950s.

One piece has us stumped, though - hanging out of the right side behind the carriage is a thin strap/flat string with a metal bracket on the end.  Picture here:
<a href="https://ibb.co/Bq44nXT"><img src="https://i.ibb.co/J5xx3fr/94467-E0-A-0398-46-A0-BE32-17-FCE564-CB5-C.jpg" alt="94467-E0-A-0398-46-A0-BE32-17-FCE564-CB5-C" border="0"></a>

Forgive our ignorance, but *what is this*? Can’t find mention in the original manual or anything similar in typewriter restoration videos etc.