I edited your post. Please, next time format your post according to the following guide: How to format your forum posts
In short: please, use </> button to share codes, terminal outputs, error messages or anything that can contain special characters which would be interpreted by the MarkDown filter. Use the preview feature to make sure your text is formatted as you would expect it and check your post after you have sent it so you can still fix it.
How exactly did you change the html file and how did you “restart” the container? You should not edit files directly inside containers. Instead, you can build a new Docker image and change the definition of the swarm service to use the new image. If you have multiple swarm nodes or you build the image on another machine, you should also have Docker registry.where you push you image and swarm can pull it from that registry. If you don’t do it this way and you kill the container, swarm will recreate it, because this is its job and the new container will not have any of the modifications you made in a previous container.