Naval ensign and jack of Austria, 1926-1934 or 1935. (The source used for this depiction of the flag, here http://zeljko-heimer-fame.from.hr/descr/at-1918.html, claims the flag as ceasing to be used in 1935. However the Austrian government changed its coat of arms in 1934, including on its flags, so that claim that it continued until 1935 may be a mistake.
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