ArduinoIDE 2.0.0-beta3: Cannot send from serial monitor to a connected BT HC-05

I am on Ubuntu20.04LTS and a downloaded the arduino ide 20.0.0 beta-3. I have a Arduino Mega whose serial port 2 is connected to a HC-05 BT module. But, I cannot send from the serial monitor to the arduino. When I type something in the entry and hit enter, nothing happens. I ran the same code in the ArudinoIDE-1.18.13 and it works there. Any suggestions? or am I missing something very obvious?
#include <LiquidCrystal_PCF8574.h>

LiquidCrystal_PCF8574 lcd(0x3F);

String incomingMsg;

void setup() {
lcd.begin(16, 2);


void loop() {
if (Serial2.available()) {

incomingMsg = Serial2.readString();

lcd.setCursor(0, 0);

if (Serial.available()) {

Hello @crfhnyviirshc8fajeyivbysgkucnliu. There is an unfortunate change to the Serial Monitor UI compared to the classic Arduino IDE. You now must use Ctrl + Enter instead of just Enter to send.


You now must use Ctrl + Enter instead of just Enter to send.

Another unnecessary complication compared with the original IDE

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I agree. I have requested that the developers investigate how this situation can be improved. I know there is a plan to to a major reworking of the Serial Monitor, so I suspect there is no point in messing with the current one:

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In addition to the more general rewrite plans linked to above, there are now some additional dedicated issues used by the developers to track the specific changes to the Serial Monitor UI:

and another about clearly documenting any persistent Serial Monitor UI changes: