Incorrect username prevents search from taking place without URL edit

Expected behavior

As there is validation to allow you check the username I would expect that when a user hasn't entered a username which meets the validation requirements a user should not be able to submit the search.

Actual behavior

When you enter a username which doesn't exist and you submit the search the search field disappears and you get the search field back unless you edit the URL back to steem.show

How to reproduce

1. Go to http://steem.show
2. Within the search field enter a username that doesn't exist such as '#'
3. The search field will disappear and you won't be able to get it to return unless you remove the search parameters and return the URL to steem.show

Enviroment

• Browser: Version 64.0.3282.186 (Official Build) (64-bit)
• Operating system: MacOS HighSierra Version 10.13 (17A365)

Recording Of The Bug

A recording of the bug can be found here: https://d.tube/#!/v/tobias-g/hpwy8zap