Steps to reproduce

• Load https://www.mediawiki.org/wiki/Special:Search with a slow internet connection.
• Start typing a few characters into the big search field as soon as the search field is visible.
• Wait until the JavaScript is loaded and initialized.
• Current behavior: You have to enter a further character. Then the search suggestions gets loaded and the search suggestions box are shown.
• Expected behavior: The search suggestion engine loads the search suggestions of the already typed characters on initializing the JavaScript. The search suggestion box gets shown automatically as soon as the JavaScript and the search suggestions are loaded.

For module jquery.suggestions for the small search field this was implemented in T223422.