I'm sorry to hear that the search bar is missing for you. For positive identification, are you able to provide a before and after screenshot of what you're seeing? Please also confirm what your screen resolution is set to (e.g. 1366x768).
From my experience, if you shrink your browser window width to a certain size, then the responsive web UI is displayed and you'll see what looks like this:
Does this match what you're seeing?
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