No, that's not a bug. You don't need to specify the script of the font there, you specify it in the Left Panel or in the Settings > General > Charsets.
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Goto settings - output settings select eg ssa (tab cosmetics)
set font - script
change to greek save and exit.
if you reopen the program the script remains western ...
No, that's not a bug. You don't need to specify the script of the font there, you specify it in the Left Panel or in the Settings > General > Charsets.