diff --git a/platformio.ini b/platformio.ini
index b8ad836e6..b081f3990 100755
--- a/platformio.ini
+++ b/platformio.ini
@@ -51,12 +51,14 @@ build_flags               = -D NDEBUG
 
 [core_2_3_0]
 ; *** Esp8266 core for Arduino version 2.3.0
+; *** W A R N I N G ! *** old outdated Arduino Esp8266 core with many security issues! NOT recommended to use. NO SUPPORT!
 platform                  = espressif8266@1.5.0
 build_flags               = ${esp82xx_defaults.build_flags}
                             -Wl,-Tesp8266.flash.1m0.ld
 
 [core_2_4_2]
 ; *** Esp8266 core for Arduino version 2.4.2
+; *** W A R N I N G ! *** old outdated Arduino Esp8266 core with security issues. NOT recommended to use. NO SUPPORT!
 platform                  = espressif8266@1.8.0
 build_flags               = ${esp82xx_defaults.build_flags}
                             -Wl,-Teagle.flash.1m0.ld
@@ -70,7 +72,7 @@ build_flags               = ${esp82xx_defaults.build_flags}
                             -DVTABLES_IN_FLASH
 
 [core_pre]
-; *** Arduino Esp8266 core pre 2.6.x for Tasmota (mqtt reconnects fixed)
+; *** Arduino Esp8266 core pre 2.6.x for Tasmota (recommended version, no known issues)
 platform                  = https://github.com/Jason2866/platform-espressif8266.git#Tasmota
 build_flags               = ${esp82xx_defaults.build_flags}
                             -Wl,-Tesp8266.flash.1m.ld
@@ -107,7 +109,7 @@ build_flags               = ${esp82xx_defaults.build_flags}
 ;                           -lstdc++-exc
 
 [core_pre_ipv6]
-; *** Arduino Esp8266 core pre 2.6.x for Tasmota (mqtt reconnects fixed)
+; *** Arduino Esp8266 core pre 2.6.x IPv6 for Tasmota (use ONLY if you need IPv6, experimental!)
 platform                  = https://github.com/Jason2866/platform-espressif8266.git#Tasmota
 build_flags               = ${esp82xx_defaults.build_flags}
                             -Wl,-Tesp8266.flash.1m.ld