A Postcrossing correspondant noticed me the French background behind the postage stamp he used on his postcard:
The building is the home of the Hong Kong Special Administrative Region's Court of Final Appeal, the equivalent of the United States Supreme Court and the Cassation Court in France.
From 1915 to 1963, it was the headquarters of the French Mission in the British colony. After that, it was sold to the Hong Kong government. This Mission added the cupola. Historically, the place was historically remarkable as the residence of the first British governor in the 1840s even if the current appearance was constructed in the 1917.
This 2.60 dollar stamp was teamed with two definitive Bird stamps to reach the three dollars of the airmail rate to France (around 0.30 euro or 0,38 US dollar believing XE). It is part of a four stamp series on the Hong Kong judiciary system, issued 27 November 2008.