https://trac.ffmpeg.org/ticket/10722

Index: ffmpeg-6.1/libavcodec/librsvgdec.c
===================================================================
--- ffmpeg-6.1.orig/libavcodec/librsvgdec.c	2023-11-11 03:25:17.000000000 +0300
+++ ffmpeg-6.1/libavcodec/librsvgdec.c	2023-12-05 01:05:25.049963387 +0300
@@ -88,12 +88,14 @@ static int librsvg_decode_frame(AVCodecC
     ret = ff_set_dimensions(avctx, dimensions.width, dimensions.height);
     if (ret < 0)
         goto end;
 
     avctx->pix_fmt = AV_PIX_FMT_RGB32;
+#if LIBRSVG_MAJOR_VERSION > 2 || LIBRSVG_MAJOR_VERSION == 2 && LIBRSVG_MINOR_VERSION >= 52
     viewport.width = dimensions.width;
     viewport.height = dimensions.height;
+#endif
 
     ret = ff_get_buffer(avctx, frame, 0);
     if (ret < 0)
         goto end;