[racket-users] change frame style caption ?

hello racketers I am playing for fun with a racket toy clock and I have some little requests is it possible to change the style (caption/no-caption) of a frame% after creation ? is it possible to create transparent windows ? thanks for help -- You

[racket-users] ffi-lib: couldn't open "libobjc.dylib

I've been away from racket for a while and started using it yesterday with 7.2. I get the following with 7.2, 7.1 and 6.12 (the latter used to work fine). This is on Mac OSX 10.14.4 updated around 3/20/2019 (based on the timestamps on the files). 693$ racket Welcome to Racket v7.2. > (require