The Corcoran Theatre neon marquee, 1939
This still image comes from a home movie at https://archive.org/details/chi_000061 It is at 11:04 to 11:19, just before Christmas 1939. The start of the film showcases the Golden Gate International Exposition. The film shows the neon lights cycling through their sequence, though the two shots are taken a distance from the theatre. Copyright status is not indicated on archive.org, but it is likely now public domain. This might shed some new light on the theatre, if it was previously unknown how early it was operating, it looks like we can now say it was certainly there in 1939. ps: the sign looks exactly like the sign in the 2001 photo from the Bob Meza collection over at CinemaTour.com
No one has favorited this photo yet