When using the .NET AWSSDK connected to localstack and querying cloudwatch logs e.g. 
 var logClient = new AmazonCloudWatchLogsClient(new AmazonCloudWatchLogsConfig()
            {
                ServiceURL = "http://localhost:4586",
                UseHttp = true,
                AuthenticationRegion = "eu-central-1",
            });
            var logGroupName = @"/aws/lambda/f1";
            var events = logClient.FilterLogEventsAsync(new FilterLogEventsRequest()
            {
                LogGroupName = logGroupName,
            }).GetAwaiter().GetResult();

The response is returned from the server but cannot be parsed by the SDK client code because the response's content-type header is text/html when it should be application/x-amz-json-1.1.  This confirmed using Fiddler traces comparing the response from localstack to the response from AWS in the cloud. Can this be fixed easily?
import unittest
from localstack.utils.aws import aws_stack
from localstack.utils.common import short_uid
class CloudWatchLogsTest(unittest.TestCase):
    def test_put_events_multibyte_msg(self):
        client = aws_stack.connect_to_service('logs')
        group = 'g-%s' % short_uid()
        stream = 's-%s' % short_uid()
        response = client.create_log_group(logGroupName=group)
        self.assertEquals(response['ResponseMetadata']['HTTPStatusCode'], 200)
        response = client.create_log_stream(logGroupName=group, logStreamName=stream)
        self.assertEquals(response['ResponseMetadata']['HTTPStatusCode'], 200)
        
        body_msg = '🙀 - 参よ - 日本語'
        events = [{
            'timestamp': 1234567,
            'message': body_msg
        }]
        response = client.put_log_events(logGroupName=group, logStreamName=stream, logEvents=events)
        self.assertEquals(response['ResponseMetadata']['HTTPStatusCode'], 200)
        events = client.get_log_events(logGroupName=group, logStreamName=stream)['events']
        self.assertEquals(events[0]['message'], body_msg)