diff --git a/configure b/configure
index 7b8ce13..85c96d4 100755
--- a/configure
+++ b/configure
@@ -303,6 +303,7 @@ External library support:
   --enable-decklink        enable Blackmagic DeckLink I/O support [no]
   --enable-mbedtls         enable mbedTLS, needed for https support
                            if openssl, gnutls or libtls is not used [no]
+  --enable-librist         enable RIST via librist [no]
   --enable-mediacodec      enable Android MediaCodec support [no]
   --enable-mediafoundation enable encoding via MediaFoundation [auto]
   --enable-libmysofa       enable libmysofa, needed for sofalizer filter [no]
diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
index dfba8e6..b08abc6 100644
--- a/fftools/ffmpeg_opt.c
+++ b/fftools/ffmpeg_opt.c
@@ -3371,7 +3371,7 @@ fail:
 
 static int opt_progress(void *optctx, const char *opt, const char *arg)
 {
-    progress_avio = avio;
+    progress_avio = NULL;
     return 0;
 }