📄 java-checks/src/main/java/org/sonar/java/checks/JavaFootprint.java:34
The new EndWithDetector(0.9, ';') is given a probability (0.9) that is exactly equal to CommentedOutCodeLineCheck.THRESHOLD (0.9). The FP-removal behaviour relies entirely on CodeRecognizer.isLineOfCode using a strict greater-than comparison (recognition(line) - threshold > 0): a line whose only code signal is a trailing ';' yields recognition == 0.9, which is NOT > 0.9, so it is correctly ignored. This is the intended fix, but the coupling is implicit and brittle:

• If THRESHOLD is ever changed (e.g. to 0.85 or 0.95), or if the upstream commons library changes the comparison to >=, the rule will either start re-emitting all the semicolon FPs again or stop detecting other code, with no test in this file pinning the relationship.
  Suggested fix: add a code comment in JavaFootprint explaining that 0.9 is deliberately set equal to the recognizer threshold so that a trailing ';' alone never crosses it, and ideally reference the THRESHOLD constant so the dependency is visible. This protects the intent against future edits to either value.