This is featured in the Swedish and Norwegian version of "From All of Us to All of You! (1958)", which is shown on TV every Christmas Eve.
The song that Donald quacks while bathing in "Mickey's Trailer" from 1938 is "When It's Springtime in the Rockies".
The song that Goofy sings while driving in "Mickey's Trailer" from 1938 is "She'll Be Coming 'Round the Mountain".
"Mickey's Trailer" from 1938 was incorporated into the 1983 film "The Outsiders (1983)", in which characters watched it on TV, during the scenes where Goofy was feeding the Cow and when Donald was in bed.
"Mickey's Trailer" from 1938 is the 100th Mickey Mouse Cartoon released in the Mickey Mouse film series, if the three Donald Duck Cartoons that were originally part of the Mickey Mouse film series, are like they were a bit later counted to the Donald Duck film series.