viewtopic.php?f=3&t=60676
viewtopic.php?f=3&t=55280
It wasn't fixed for "gtk2" in 5.31 and it's back again in 5.40 (b8 for sure):
PB 5.31 SpinGadget with "gtk2" subsystem (default) /spin at the bottom created with API/:

PB 5.31 SpinGadget with "gtk3" subsystem:

PB 5.40 SpinGadget with "gtk2" subsystem /spin at the bottom created with API/:

PB 5.40 SpinGadget with "gtk3" subsystem (default):
