In the spec of StructuredTaskScope::open, the sentence
"If a timeout is set then it starts when the scope is opened. If the timeout expires before the scope has joined then the scope is cancelled and the join method throws StructuredTaskScope.TimeoutException."
could use a small enhancement to make the wording clearer and consistent, something like:
"If the timeout expires before or while waiting ....... "

Java SE 25 spec: https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/concurrent/StructuredTaskScope.html#open(java.util.concurrent.StructuredTaskScope.Joiner,java.util.function.Function)

Also a small issue in the following sentence as well (Java SE 26 spec only):

“The Joiner's StructuredTaskScope.Joiner.onTimeout() method is invoked to throw optionally throw TimeoutException.”

Might be corrected to :

“the Joiner's StructuredTaskScope.Joiner.onTimeout() method is invoked to optionally throw TimeoutException.”