From 77ec2354e8f46d5ef149d1dcaf25f51c04149137 Mon Sep 17 00:00:00 2001
From: Travis Ralston <travpc@gmail.com>
Date: Tue, 5 Sep 2023 13:09:04 -0600
Subject: [PATCH] Fix Content-Disposition handling

---
 api/_routers/98-use-rcontext.go |  2 +-
 util/mime.go                    | 36 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/api/_routers/98-use-rcontext.go b/api/_routers/98-use-rcontext.go
index bd6bf03b..18c678c1 100644
--- a/api/_routers/98-use-rcontext.go
+++ b/api/_routers/98-use-rcontext.go
@@ -112,7 +112,7 @@ beforeParseDownload:
 			if contentType == "" {
 				disposition = "attachment"
 			} else {
-				if util.HasAnyPrefix(contentType, []string{"image/", "audio/", "video/", "text/plain"}) {
+				if util.CanInline(contentType) {
 					disposition = "inline"
 				} else {
 					disposition = "attachment"
diff --git a/util/mime.go b/util/mime.go
index 58876549..8d34d03f 100644
--- a/util/mime.go
+++ b/util/mime.go
@@ -16,3 +16,39 @@ func ExtensionForContentType(ct string) string {
 	}
 	return ".bin"
 }
+
+func CanInline(ct string) bool {
+	ct = FixContentType(ct)
+	return ArrayContains(InlineContentTypes, ct)
+}
+
+var InlineContentTypes = []string{
+	// Types are inherited from https://github.com/matrix-org/synapse/pull/15988
+
+	"text/css",
+	"text/plain",
+	"text/csv",
+	"application/json",
+	"application/ld+json",
+	"image/jpeg",
+	"image/gif",
+	"image/png",
+	"image/apng",
+	"image/webp",
+	"image/avif",
+	"video/mp4",
+	"video/webm",
+	"video/ogg",
+	"video/quicktime",
+	"audio/mp4",
+	"audio/webm",
+	"audio/aac",
+	"audio/mpeg",
+	"audio/ogg",
+	"audio/wave",
+	"audio/wav",
+	"audio/x-wav",
+	"audio/x-pn-wav",
+	"audio/flac",
+	"audio/x-flac",
+}