[crashryan]

My guess is that this supplement was published sometime between 1933-1937. My reasoning: "The Skipper" itself ran from 1930 to 1941. The cycle of American gangster films began around 1932 and began petering out around 1935 after Cagney quit the gangs and became a G-Man. Note that the editors assume their readers aren't familiar with "American film slang" but omit "G-Man." (Plus they get a couple of them wrong.) All that suggests 1933-1934, or a year or two later if the editors were behind the times. I've noticed that war themes became increasingly popular in story papers around 1937-1938 and there are no military-themed pieces here. So I conjecture this supplement would have been published no later than 1936-1937. Of course this is all guesswork!

Link to the book: The Skipper Tricky Tips

[The Australian Panther]

The cycle of American gangster films began around 1932 and began petering out around 1935 after Cagney quit the gangs and became a G-Man. 

Interesting observation. Never saw that before. I think you are basically right.

That time tho is the beginning of the NOIR film era, where the subject area was crime and criminals - organized or otherwise - and the subject was individuals having to deal with the consequences of bad choices or unforseen circumstances.
Also, suggest the 'Gangster' film morphed into the 'Caper'  film which continues today. Examples, the Ocean films and their spin-offs and even the Han Solo standalone film. 
Interestingly I can think of Gangster comics and NOIR comics, but not 'Caper' comics. Anybody have any suggestions?

Cheers!   

Cheers!