Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32F107xx/UART5/CR3#0x0
UART5 CR3
Error interrupt enable
IrDA mode enable
IrDA low-power
Half-duplex selection
DMA enable transmitter
https://github.com/cmsis-svd/cmsis-svd-data