diff --git a/include/haproxy/htx-t.h b/include/haproxy/htx-t.h
index 00703412d..404a66e80 100644
--- a/include/haproxy/htx-t.h
+++ b/include/haproxy/htx-t.h
@@ -142,7 +142,7 @@
 #define HTX_FL_NONE              0x00000000
 #define HTX_FL_PARSING_ERROR     0x00000001 /* Set when a parsing error occurred */
 #define HTX_FL_PROCESSING_ERROR  0x00000002 /* Set when a processing error occurred */
-/* 0x00000004 unused */
+#define HTX_FL_FRAGMENTED        0x00000004 /* Set when the HTX buffer is fragmented */
 #define HTX_FL_PROXY_RESP        0x00000008 /* Set when the response was generated by HAProxy */
 #define HTX_FL_EOM               0x00000010 /* Set when end-of-message is reached from the HTTP point of view
 					     * (at worst, on the EOM block is missing)
diff --git a/src/htx.c b/src/htx.c
index 05ba03ba9..8c6e368e7 100644
--- a/src/htx.c
+++ b/src/htx.c
@@ -79,6 +79,7 @@ struct htx_blk *htx_defrag(struct htx *htx, struct htx_blk *blk, uint32_t blkinf
 	htx->tail = new - 1;
 	htx->head_addr = htx->end_addr = 0;
 	htx->tail_addr = addr;
+	htx->flags &= ~HTX_FL_FRAGMENTED;
 	memcpy((void *)htx->blocks, (void *)tmp->blocks, htx->size);
 
 	return ((blkpos == -1) ? NULL : htx_get_blk(htx, blkpos));
@@ -339,10 +340,10 @@ struct htx_blk *htx_remove_blk(struct htx *htx, struct htx_blk *blk)
 
 	/* This is the last block in use */
 	if (htx->head == htx->tail) {
-		uint32_t flags = htx->flags; /* Preserve flags */
+		uint32_t flags = (htx->flags & ~HTX_FL_FRAGMENTED); /* Preserve flags except FRAGMENTED */
 
 		htx_reset(htx);
-		htx->flags |= flags;
+		htx->flags = flags; /* restore flags */
 		return NULL;
 	}
 
@@ -368,6 +369,9 @@ struct htx_blk *htx_remove_blk(struct htx *htx, struct htx_blk *blk)
 		blk = NULL;
 		goto end;
 	}
+	else
+		htx->flags |= HTX_FL_FRAGMENTED;
+
 	blk = htx_get_blk(htx, pos+1);
 
   end:
@@ -459,7 +463,7 @@ struct htx_ret htx_drain(struct htx *htx, uint32_t count)
 	struct htx_ret htxret = { .blk = NULL, .ret = 0 };
 
 	if (count == htx->data) {
-		uint32_t flags = htx->flags;
+		uint32_t flags = (htx->flags & ~HTX_FL_FRAGMENTED); /* Preserve flags except FRAGMENTED */
 
 		htx_reset(htx);
 		htx->flags = flags; /* restore flags */