Place onion, bell pepper, cilantro, and jalapeños in the bowl of a food processor; pulse until finely chopped. Add tomatoes; pulse several times until tomatoes are coarsely chopped. Transfer to a bowl with a tight-fitting lid.

Whisk olive oil, red wine vinegar, lime juice, and salt together in a small bowl until vinaigrette well combined.

Pour vinaigrette over tomato mixture; stir well. Cover; refrigerate before serving for at least 1 hour.