User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0

Steps to reproduce:

• Define a search shortcut, such as "yt" for youtube.com.
• In the address bar (Ctrl+L) type "yt "
• Press Enter

Actual results:

• Immediately after typing "yt ", the string "yt " changes into a blue box displaying YouTube
• After hitting Enter nothing happens.

Expected results:

• Changing the string into the search engine to be searched is apparently a new feature. I am OK with this.
• After hitting Enter I expect to be taken to the front page of the Site to be searched: in this case "youtube.com"
• This is the functionality of previous versions.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.