The container log viewer losts initals every line

Expected behavior

This is docker logs showing:

Actual behavior

This is portainer showing:

Reproduce the Bug

1. Get a docker image like mysql

docker pull mysql:latest

2.Run it

docker run -it -d --name mysql -e MYSQL_ROOT_PASSWORD=123456  mysql

3.Open portainer in browser and log in. Go to the mysql container log we just created.