After changing to "default_envs = fysetc_STM32F1" I have:
Error: Unknown environment names 'fysetc_STM32F1'. Valid names are 'STM32F103CB_malyan, rambo, mega2560, mks_robin_lite, esp32, sanguino1284p, STM32F103RC, include_tree, FYSETC_S6, rumba32_f446ve, mks_robin_nano, BIGTREE_SKR_PRO, at90usb1286_dfu, STM32F103RC_fysetc, STM32F407VE_black, teensy31, at90usb1286_cdc, STM32F103VE_GTM32, mks_robin_mini, STM32F103RE_btt, FLYF407ZG, LPC1768, STM32F7, FYSETC_F6_14, STM32F103RC_btt_512K, jgaurora_a5s_a1, STM32F103RC_btt_512K_USB, STM32F103RE_btt_USB, linux_native, LPC1769, STM32F103RE, STM32F401VE_STEVAL, teensy35, STM32F4, STM32F103VE_longer, SAMD51_grandcentral_m4, STM32F103RC_btt_USB, mega1280, sanguino644p, melzi_optiboot, DUE_debug, mks_robin_pro, BIGTREE_BTT002, FYSETC_F6_13, STM32F103RC_btt, ARMED, DUE, mks_robin, melzi, chitu_f103, rumba32_mks, BIGTREE_GTR_V1_0, DUE_USB, mks_robin_lite3'
Help please !
Thanks
Tom