URL path escapes '@' symbol, which breaks the url

Description

I have theia running under JupterLab, the username in the url is an email address and contains an @, for example:

/users/rayh@example.com/theia

While I can load the page, the websocket url escapes the @ and therefore breaks the url and the websocket connection cannot be established.

In webpack:///./node_modules/vscode-uri/lib/esm/index.js - if I flip skipEncoding to true, the url now works, but i suspect this will not encode the request params.

Here is the failing connection:

Reproduction Steps

Simplest test would be to deploy theia under a url path that contains an '@'

OS and Theia version: Theia 0.5.0 running in Ubutnu 18.04.1 LTS