diff --git a/core/embed/lib/image.c b/core/embed/lib/image.c
index 6b60630a3..874e9d39e 100644
--- a/core/embed/lib/image.c
+++ b/core/embed/lib/image.c
@@ -26,7 +26,9 @@
 #include "image.h"
 #include "model.h"
 
-_Static_assert(VENDOR_HEADER_MAX_SIZE + IMAGE_HEADER_SIZE <= IMAGE_CHUNK_SIZE);
+_Static_assert(VENDOR_HEADER_MAX_SIZE + IMAGE_HEADER_SIZE <= IMAGE_CHUNK_SIZE,
+               "The size of the firmware headers must be less than or equal to "
+               "IMAGE_CHUNK_SIZE");
 
 const uint8_t BOOTLOADER_KEY_M = 2;
 const uint8_t BOOTLOADER_KEY_N = 3;