diff --git a/platformio.ini b/platformio.ini
index e46b9ec5..74cf55ca 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -10,7 +10,8 @@
 # ------------------------------------------------------------------------------
 
 # CI binaries
-default_envs = nodemcuv2, esp8266_2m, esp01_1m_full, esp32dev, esp32_eth # ESP32 variant builds are temporarily excluded from CI due to toolchain issues on the GitHub Actions Linux environment
+;; default_envs = nodemcuv2, esp8266_2m, esp01_1m_full, esp32dev, esp32_eth # ESP32 variant builds are temporarily excluded from CI due to toolchain issues on the GitHub Actions Linux environment
+default_envs = nodemcuv2, esp8266_2m, esp01_1m_full, esp32dev, esp32_eth, lolin_s2_mini, esp32c3dev, esp32s3dev_8MB
 
 # Release binaries
 ; default_envs = nodemcuv2, esp8266_2m, esp01_1m_full, esp32dev, esp32_eth, lolin_s2_mini, esp32c3dev, esp32s3dev_8MB
@@ -249,6 +250,7 @@ lib_deps =
 ;; You need to completely erase your device (esptool erase_flash) first, then install the "V4" build from VSCode+platformio.
 platform = espressif32@5.2.0
 platform_packages =
+  toolchain-riscv32-esp @ 8.4.0+2021r2-patch5 ; required for platform version < 5.3.0, remove this line when upgrading to platform >=5.3.0
 build_flags = -g
   -Wshadow=compatible-local ;; emit warning in case a local variable "shadows" another local one
   -DARDUINO_ARCH_ESP32 -DESP32
@@ -264,6 +266,7 @@ lib_deps =
 ;; generic definitions for all ESP32-S2 boards
 platform = espressif32@5.2.0
 platform_packages =
+  toolchain-riscv32-esp @ 8.4.0+2021r2-patch5 ; required for platform version < 5.3.0, remove this line when upgrading to platform >=5.3.0
 build_flags = -g
   -DARDUINO_ARCH_ESP32
   -DARDUINO_ARCH_ESP32S2
@@ -283,6 +286,7 @@ lib_deps =
 ;; generic definitions for all ESP32-C3 boards
 platform = espressif32@5.2.0
 platform_packages =
+  toolchain-riscv32-esp @ 8.4.0+2021r2-patch5 ; required for platform version < 5.3.0, remove this line when upgrading to platform >=5.3.0
 build_flags = -g
   -DARDUINO_ARCH_ESP32
   -DARDUINO_ARCH_ESP32C3
@@ -301,6 +305,7 @@ lib_deps =
 ;; generic definitions for all ESP32-S3 boards
 platform = espressif32@5.2.0
 platform_packages =
+  toolchain-riscv32-esp @ 8.4.0+2021r2-patch5 ; required for platform version < 5.3.0, remove this line when upgrading to platform >=5.3.0
 build_flags = -g
   -DESP32
   -DARDUINO_ARCH_ESP32