GLib-based programs started printing GLib-DEBUG: posix_spawn avoided (fd close requested)
Programs that use GLib and have their own message handler started to print
GLib-DEBUG: posix_spawn avoided (fd close requested)
and similar messages in GLib 2.58. Please remove the messages.
Note that I have read !337 (closed) and do not understand how it solved anything. There is no ‘time to fix handlers’ in existing software; nothing will fix already existing versions of software. It can be only done by modifying the software and releasing new versions. So the behaviour is not backward compatible.