Pass content-disposition header through file proxy

src/web/routes/download-matrix.js

@@ -98,6 +98,11 @@ as.router.get(`/download/matrix/:server_name/:media_id`, defineEventHandler(asyn
 	setResponseHeader(event, "Content-Type", contentType)
 	setResponseHeader(event, "Transfer-Encoding", "chunked")
 
+	const contentDisposition = res.headers.get("content-disposition")
+	if (contentDisposition) {
+		setResponseHeader(event, "Content-Disposition", contentDisposition)
+	}
+
 	if (res.ok && query.success) {
 		return MEDIA_THUMBNAIL_PRESETS[query.data.preset](res.body)
 	} else {

src/web/routes/download-matrix.test.js

@@ -30,12 +30,13 @@ test("web download matrix: works if a known attachment", async t => {
 		api: {
 			// @ts-ignore
 			async getMedia(mxc, init) {
-				return new Response("", {status: 200, headers: {"content-type": "image/png"}})
+				return new Response("", {status: 200, headers: {"content-type": "image/png", "content-disposition": `attachment; filename="wa.png"`}})
 			}
 		}
 	})
 	t.equal(event.node.res.statusCode, 200)
 	t.equal(event.node.res.getHeader("content-type"), "image/png")
+	t.equal(event.node.res.getHeader("content-disposition"), `attachment; filename="wa.png"`)
 })
 
 /**