diff --git a/thirdparty/README.md b/thirdparty/README.md
index 738835c70a7..f36b53f1e33 100644
--- a/thirdparty/README.md
+++ b/thirdparty/README.md
@@ -178,18 +178,21 @@ Files extracted from upstream source:
 ## libsimplewebm
 
 - Upstream: https://github.com/zaps166/libsimplewebm
-- Version: git (05cfdc2, 2016)
-- License: MIT, BSD-3-Clause
+- Version: git (fe57fd3, 2019)
+- License: MIT (main), BSD-3-Clause (libwebm)
+
+This contains libwebm, but the version in use is updated from the one used by libsimplewebm,
+and may have *unmarked* alterations from that.
 
 Files extracted from upstream source:
 
-TODO.
+- all the .cpp, .hpp files in the main folder except `example.cpp`
+- LICENSE
 
 Important: Some files have Godot-made changes.
 They are marked with `// -- GODOT start --` and `// -- GODOT end --`
 comments.
 
-
 ## libtheora
 
 - Upstream: https://www.theora.org
diff --git a/thirdparty/libsimplewebm/OpusVorbisDecoder.cpp b/thirdparty/libsimplewebm/OpusVorbisDecoder.cpp
index c9e71eb733e..b5824b17be8 100644
--- a/thirdparty/libsimplewebm/OpusVorbisDecoder.cpp
+++ b/thirdparty/libsimplewebm/OpusVorbisDecoder.cpp
@@ -122,6 +122,7 @@ bool OpusVorbisDecoder::getPCMS16(WebMFrame &frame, short *buffer, int &numOutSa
 	return false;
 }
 
+// -- GODOT begin --
 bool OpusVorbisDecoder::getPCMF(WebMFrame &frame, float *buffer, int &numOutSamples) {
 	if (m_vorbis) {
 		m_vorbis->op.packet = frame.buffer;
@@ -158,6 +159,7 @@ bool OpusVorbisDecoder::getPCMF(WebMFrame &frame, float *buffer, int &numOutSamp
 	}
 	return false;
 }
+// -- GODOT end --
 
 bool OpusVorbisDecoder::openVorbis(const WebMDemuxer &demuxer)
 {
diff --git a/thirdparty/libsimplewebm/OpusVorbisDecoder.hpp b/thirdparty/libsimplewebm/OpusVorbisDecoder.hpp
index b7619d6a251..f285b3fbd61 100644
--- a/thirdparty/libsimplewebm/OpusVorbisDecoder.hpp
+++ b/thirdparty/libsimplewebm/OpusVorbisDecoder.hpp
@@ -44,8 +44,10 @@ public:
 	{
 		return m_numSamples;
 	}
-	bool getPCMF(WebMFrame &frame, float *buffer, int &numOutSamples);
 	bool getPCMS16(WebMFrame &frame, short *buffer, int &numOutSamples);
+// -- GODOT begin --
+	bool getPCMF(WebMFrame &frame, float *buffer, int &numOutSamples);
+// -- GODOT end --
 
 private:
 	bool openVorbis(const WebMDemuxer &demuxer);
diff --git a/thirdparty/libsimplewebm/VPXDecoder.cpp b/thirdparty/libsimplewebm/VPXDecoder.cpp
index 3f77b8f5cd6..e2606f83ba0 100644
--- a/thirdparty/libsimplewebm/VPXDecoder.cpp
+++ b/thirdparty/libsimplewebm/VPXDecoder.cpp
@@ -33,7 +33,8 @@
 VPXDecoder::VPXDecoder(const WebMDemuxer &demuxer, unsigned threads) :
 	m_ctx(NULL),
 	m_iter(NULL),
-	m_delay(0)
+	m_delay(0),
+	m_last_space(VPX_CS_UNKNOWN)
 {
 	if (threads > 8)
 		threads = 8;
@@ -86,6 +87,11 @@ VPXDecoder::IMAGE_ERROR VPXDecoder::getImage(Image &image)
 	IMAGE_ERROR err = NO_FRAME;
 	if (vpx_image_t *img = vpx_codec_get_frame(m_ctx, &m_iter))
 	{
+		// It seems to be a common problem that UNKNOWN comes up a lot, yet FFMPEG is somehow getting accurate colour-space information.
+		// After checking FFMPEG code, *they're* getting colour-space information, so I'm assuming something like this is going on.
+		// It appears to work, at least.
+		if (img->cs != VPX_CS_UNKNOWN)
+			m_last_space = img->cs;
 		if ((img->fmt & VPX_IMG_FMT_PLANAR) && !(img->fmt & (VPX_IMG_FMT_HAS_ALPHA | VPX_IMG_FMT_HIGHBITDEPTH)))
 		{
 			if (img->stride[0] && img->stride[1] && img->stride[2])
@@ -95,6 +101,7 @@ VPXDecoder::IMAGE_ERROR VPXDecoder::getImage(Image &image)
 
 				image.w = img->d_w;
 				image.h = img->d_h;
+				image.cs = m_last_space;
 				image.chromaShiftW = img->x_chroma_shift;
 				image.chromaShiftH = img->y_chroma_shift;
 
@@ -119,7 +126,9 @@ VPXDecoder::IMAGE_ERROR VPXDecoder::getImage(Image &image)
 
 /**/
 
+// -- GODOT begin --
 #if 0
+// -- GODOT end --
 
 static inline int ceilRshift(int val, int shift)
 {
@@ -139,4 +148,7 @@ int VPXDecoder::Image::getHeight(int plane) const
 	return ceilRshift(h, chromaShiftH);
 }
 
+// -- GODOT begin --
 #endif
+// -- GODOT end --
+
diff --git a/thirdparty/libsimplewebm/VPXDecoder.hpp b/thirdparty/libsimplewebm/VPXDecoder.hpp
index 61083958710..5071b069cb1 100644
--- a/thirdparty/libsimplewebm/VPXDecoder.hpp
+++ b/thirdparty/libsimplewebm/VPXDecoder.hpp
@@ -37,12 +37,17 @@ public:
 	class Image
 	{
 	public:
+// -- GODOT begin --
 #if 0
+// -- GODOT end --
 		int getWidth(int plane) const;
 		int getHeight(int plane) const;
+// -- GODOT begin --
 #endif
+// -- GODOT end --
 
 		int w, h;
+		int cs;
 		int chromaShiftW, chromaShiftH;
 		unsigned char *planes[3];
 		int linesize[3];
@@ -75,6 +80,7 @@ private:
 	vpx_codec_ctx *m_ctx;
 	const void *m_iter;
 	int m_delay;
+	int m_last_space;
 };
 
 #endif // VPXDECODER_HPP