diff --git a/boards/adafruit-clue/doc.txt b/boards/adafruit-clue/doc.md
similarity index 99%
rename from boards/adafruit-clue/doc.txt
rename to boards/adafruit-clue/doc.md
index 72a6958561..e14598a5f2 100644
--- a/boards/adafruit-clue/doc.txt
+++ b/boards/adafruit-clue/doc.md
@@ -1,4 +1,3 @@
-/**
 @defgroup    boards_adafruit-clue Adafruit Clue
 @ingroup     boards
 @brief       Support for the Adafruit Clue
@@ -42,4 +41,3 @@ Use the `term` target to connect to the board serial port<br/>
 The `TERM_DELAY` environment variable can be used to add a delay (in second)
 before opening the serial terminal. The default value is 2s which should be
 enough in most of the situations.
- */
diff --git a/boards/adafruit-itsybitsy-nrf52/doc.txt b/boards/adafruit-itsybitsy-nrf52/doc.md
similarity index 99%
rename from boards/adafruit-itsybitsy-nrf52/doc.txt
rename to boards/adafruit-itsybitsy-nrf52/doc.md
index f0a7cebf03..d94d11b77e 100644
--- a/boards/adafruit-itsybitsy-nrf52/doc.txt
+++ b/boards/adafruit-itsybitsy-nrf52/doc.md
@@ -1,4 +1,3 @@
-/**
 @defgroup    boards_adafruit-itsybitsy-nrf52 Adafruit-Itsybitsy-nRF52
 @ingroup     boards
 @brief       Support for the Adafruit-Itsybitsy-nRF52
@@ -41,5 +40,3 @@ you may need to run `pip3 install --upgrade pip3` before being able to run `pip3
 ### Accessing STDIO
 
 The usual way to obtain a console on this board is using an emulated USB serial port.
-
- */