A Cinedrome Pop Quiz

Here's a challenge for Cinedrome's readers, just for fun.

I recently won an auction on eBay for a 16mm print. The
picture is Up in Mabel's Room (1944), directed by Allan
Dwan, based on the 1919 Broadway chestnut by Wilson
Collison and Otto Hauerbach. The movie's cast includes
Marjorie Reynolds, Dennis O'Keefe, Gail Patrick, Mischa
Auer, Charlotte Greenwood and Binnie Barnes.

But none of that is important for our purposes here. What
is important is what came with the print. The seller included
a little note thanking me for my purchase and hoping I enjoy
it. Attached to the note was a unique bookmark, consisting
of four frames of 35mm Technicolor film (plus a diagonal
slice of an additional frame at each end). The four frames
are reproduced on the left.

Now here's the challenge, in two parts: (1) Name the movie
these  frames are from; and (2) Identify the actors. The
Grand prize is unlimited bragging rights. Leave your guesses,
or any questions, in the comments. All right, ready? Go!

Next up here at Cinedrome: Shirley Temple Revisited, Part 1.