To hide the top bar or "extensions bar" or "Quick access bar" do the following:
Open the Fleksy app → Tap the menu button (top left) → Tap "Settings" → Tap "Advanced" → Enable "Swipe to Hide Extensions."
Now, inside your keyboard, swipe left on the extension bar so you are NOT on the "Highlights" extension (the one with 🔍).
Please note: You cannot hide the bar when this is present, you may need to add another extension if you don't already have one added. Extensions can be added under the "Extensions" tab inside the Fleksy App.
Once you are inside the keyboard on another extension, you can swipe down over the extensions bar to hide it. Likewise, swiping up brings it back.