Using Uppy to upload Dropbox videos to the node/express server doesnt work with more than 1 instance

i have a simple server set up, with Uppy configured with Companion and the correct keys to enable dropbox, I can access dropbox and select my file, but if I’m running more than 1 server instance, the upload doesn’t go through
I’m running the server on
uppy docs state this
configure Companion like this:

server: {
        oauthDomain: <master domain (e.g to handle your oauth>,
        validHosts: <a list of valid domains running your Companion instances. The list may also contain regex patterns. e.g ['', '(\\w+)']>

given that my website is called running a web service and everything else on default, what would be the appropriate strings or lists to add in those fields?

Hi, please see the details here for about Companion in a multi instance environment. Short story: horizontal scaling is broken currently and you need sticky sessions to marry the client to a specific companion instance.