feat(ux): show messaging when response takes longer than expected

Fixes #912.

We don't currently have any use for a dedicated page, so I ignored that part.

@ckarlof r?
Not sure if this matters, but should this be "…" vs "..."? (where one is an ellipsis and other is three periods - not sure if all fonts have the ellipsis char since we may not always be using Fira in certain locales).