Unable to upload during serial communication on Linux

■ Corresponding version  
v.2.3.0

■ Contents and Occurrence conditions  
An error occurs when uploading during serial communication on Linux.  
The error conditions are as follows.
* RL78/G23-64p FPB uses micro USB terminal for serial communication
* Upload a sketch using Arduino IDE on Linux

■ Workaround  
Please update the Arduino library.

■ Permanent measures  
Fixed in V2.3.1.