so...Find, Find+Replace text-field navigation should work like Chrome/Fire-bug console:
1. Up/Down arrows changes cursor position in multi-line text.
2. When cursor reaches begining of multi-line text then Up is used to 'Go back' find/replace history
3. When cursor reaches end of multi-line text then Down is used to 'Go forward' find/replace history AND if current text is last in history pressing Down will clear text-field.
Live example in Chrome press F12 / Console / type some js functions then navigate thru history.
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