diff --git a/lib/TasmotaSerial-2.3.3/README.md b/lib/TasmotaSerial-2.3.4/README.md
similarity index 100%
rename from lib/TasmotaSerial-2.3.3/README.md
rename to lib/TasmotaSerial-2.3.4/README.md
diff --git a/lib/TasmotaSerial-2.3.3/examples/swsertest/swsertest.ino b/lib/TasmotaSerial-2.3.4/examples/swsertest/swsertest.ino
similarity index 100%
rename from lib/TasmotaSerial-2.3.3/examples/swsertest/swsertest.ino
rename to lib/TasmotaSerial-2.3.4/examples/swsertest/swsertest.ino
diff --git a/lib/TasmotaSerial-2.3.3/keywords.txt b/lib/TasmotaSerial-2.3.4/keywords.txt
similarity index 100%
rename from lib/TasmotaSerial-2.3.3/keywords.txt
rename to lib/TasmotaSerial-2.3.4/keywords.txt
diff --git a/lib/TasmotaSerial-2.3.3/library.json b/lib/TasmotaSerial-2.3.4/library.json
similarity index 94%
rename from lib/TasmotaSerial-2.3.3/library.json
rename to lib/TasmotaSerial-2.3.4/library.json
index 46a55b7dc..271deceb0 100644
--- a/lib/TasmotaSerial-2.3.3/library.json
+++ b/lib/TasmotaSerial-2.3.4/library.json
@@ -1,6 +1,6 @@
 {
     "name": "TasmotaSerial",
-    "version": "2.3.3",
+    "version": "2.3.4",
     "keywords": [
       "serial", "io", "TasmotaSerial"
     ],
diff --git a/lib/TasmotaSerial-2.3.3/library.properties b/lib/TasmotaSerial-2.3.4/library.properties
similarity index 94%
rename from lib/TasmotaSerial-2.3.3/library.properties
rename to lib/TasmotaSerial-2.3.4/library.properties
index c99402e68..4dccb28ad 100644
--- a/lib/TasmotaSerial-2.3.3/library.properties
+++ b/lib/TasmotaSerial-2.3.4/library.properties
@@ -1,5 +1,5 @@
 name=TasmotaSerial
-version=2.3.3
+version=2.3.4
 author=Theo Arends
 maintainer=Theo Arends <theo@arends.com>
 sentence=Implementation of software serial with hardware serial fallback for ESP8266.
diff --git a/lib/TasmotaSerial-2.3.3/src/TasmotaSerial.cpp b/lib/TasmotaSerial-2.3.4/src/TasmotaSerial.cpp
similarity index 96%
rename from lib/TasmotaSerial-2.3.3/src/TasmotaSerial.cpp
rename to lib/TasmotaSerial-2.3.4/src/TasmotaSerial.cpp
index 88151a8f1..472425336 100644
--- a/lib/TasmotaSerial-2.3.3/src/TasmotaSerial.cpp
+++ b/lib/TasmotaSerial-2.3.4/src/TasmotaSerial.cpp
@@ -27,6 +27,9 @@ extern "C" {
 
 #include <TasmotaSerial.h>
 
+// for STAGE and pre-2.6, we can have a single wrapper using attachInterruptArg()
+void ICACHE_RAM_ATTR callRxRead(void *self) { ((TasmotaSerial*)self)->rxRead(); };
+
 // As the Arduino attachInterrupt has no parameter, lists of objects
 // and callbacks corresponding to each possible GPIO pins have to be defined
 TasmotaSerial *tms_obj_list[16];
@@ -105,7 +108,11 @@ TasmotaSerial::TasmotaSerial(int receive_pin, int transmit_pin, int hardware_fal
       m_bit_time = ESP.getCpuFreqMHz() * 1000000 / TM_SERIAL_BAUDRATE;
       pinMode(m_rx_pin, INPUT);
       tms_obj_list[m_rx_pin] = this;
+#if defined(ARDUINO_ESP8266_RELEASE_2_3_0) || defined(ARDUINO_ESP8266_RELEASE_2_4_2) || defined(ARDUINO_ESP8266_RELEASE_2_5_2)
       attachInterrupt(m_rx_pin, ISRList[m_rx_pin], (m_nwmode) ? CHANGE : FALLING);
+#else
+      attachInterruptArg(m_rx_pin, callRxRead, this, (m_nwmode) ? CHANGE : FALLING);
+#endif
     }
     if (m_tx_pin > -1) {
       pinMode(m_tx_pin, OUTPUT);
diff --git a/lib/TasmotaSerial-2.3.3/src/TasmotaSerial.h b/lib/TasmotaSerial-2.3.4/src/TasmotaSerial.h
similarity index 100%
rename from lib/TasmotaSerial-2.3.3/src/TasmotaSerial.h
rename to lib/TasmotaSerial-2.3.4/src/TasmotaSerial.h