@Nullable
	public Problem getFirstProblemOnLine(int line) {
		List<Problem> problems = getProblemsOnLine(line);
		if (problems.isEmpty())
			return null;
		return problems.getFirst();
	}
@param line
		Line number of problem.

@return First problem on the line.
recaf-ui/src/main/java/software/coley/recaf/ui/control/richtext/problem/ProblemTracking.java