Two Serial.begin() stops serial output for 328P

[ArminJo]

It is simple to reproduce, but here is an example: https://wokwi.com/projects/399320984336916481
I use this function to receive modbus requests at 9600 and in between to print short debug messages with 115200.
See https://wokwi.com/projects/399302567914368001 , where following Serial.begin() are disabled if
#define STANDALONE_TEST
is activated 😞

[urish]

Thanks for reporting! Have you tested this on a physical device? Does it behave differently?

[ArminJo]

I just tested it, and

Serial.begin(115200);
Serial.begin(115200);

as well as

Serial.begin(115200);
IrSender.begin(); // example for any code
Serial.begin(115200);

works on Nano hardware.