Hello @RShiv.1,
You can find what is new in STM32CubeMX 6.6.0 in this link.
Since STM32CubeMX 6.6.0 released: TrueSTUDIO, System Workbench for STM32 (SW4STM32), and the GPDSC option are removed from the list of supported IDEs in STM32CubeMX.
Note that the SW4STM32 is no more supported for all new series.
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Thank you
Kaouthar
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