chromium: "stop loading this page" button erases URL from URL bar

This is not possible because of how the web traffic works, each request have/need a resulting status and can not be stateless this is why chromium remove the address you were trying to connect to (other than the security aspect of such thing).

When you request a connection to a domain/ip, the result can be for instance: 200 (OK page load), 404 (not found), 408 (timeout) etc. when you cancel your request before reaching a state, it's obvious that the browser does not display any result/url because of the cancel action and there is no HTTP state XXX code that is meant for "cancelled request" (list of http requests).

Impossible is nothing, three possible ways of resolving this issue:

  • Create an extension for the matter
  • Patch to chromium to add an xxx state (non RFC) for cancelled requests (note that chromium require a very long time to build)
  • Decrease the default timeout (408), this is not possible on chromium without patching it, it is discussed here and here as well.
    • Acknowledge that this may introduce other non desired effect like timing-out slow sites.
    • Also note that this is doable on Firefox with network.http.connection-timeout setting.