diff --git a/packages/master/src/routes.js b/packages/master/src/routes.js
index 0843f79a..b6d7f741 100644
--- a/packages/master/src/routes.js
+++ b/packages/master/src/routes.js
@@ -259,6 +259,11 @@ async function getStream(req, res) {
 }
 
 
+const zipMimes = [
+	"application/zip",
+	"application/x-zip-compressed",
+];
+
 async function uploadSave(req, res) {
 	try {
 		res.locals.user.checkPermission("core.instance.save.upload");
@@ -319,7 +324,7 @@ async function uploadSave(req, res) {
 					requestErrors.push("instance_id must come before files uploaded");
 				}
 
-				if (fileMime !== "application/zip") {
+				if (!zipMimes.includes(fileMime)) {
 					requestErrors.push("invalid file Content-Type");
 				}
 
@@ -350,7 +355,7 @@ async function uploadSave(req, res) {
 			req.pipe(busboy);
 		});
 
-	} else if (mimeType === "application/zip") {
+	} else if (zipMimes.includes(mimeType)) {
 		let filename = req.query.filename;
 		if (typeof filename !== "string") {
 			requestErrors.push("Missing or invalid filename parameter");
diff --git a/packages/web_ui/src/components/SavesList.jsx b/packages/web_ui/src/components/SavesList.jsx
index 448577c1..bd5eb6a4 100644
--- a/packages/web_ui/src/components/SavesList.jsx
+++ b/packages/web_ui/src/components/SavesList.jsx
@@ -1,5 +1,5 @@
 import React, { useContext, useState } from "react";
-import { Button, Popconfirm, Space, Table, Tooltip, Upload } from "antd";
+import { Button, List, Popconfirm, Progress, Space, Table, Tooltip, Upload } from "antd";
 import CaretLeftOutlined from "@ant-design/icons/CaretLeftOutlined";
 import LeftOutlined from "@ant-design/icons/LeftOutlined";
 
@@ -27,6 +27,7 @@ export default function SavesList(props) {
 	let control = useContext(ControlContext);
 	let saves = useSaves(props.instance.id);
 	let [starting, setStarting] = useState(false);
+	let [uploadingFiles, setUploadingFiles] = useState([]);
 
 	const saveTable = <Table
 		size="small"
@@ -107,6 +108,38 @@ export default function SavesList(props) {
 		}}
 	/>;
 
+	function onChange(changeEvent) {
+		if (["done", "error"].includes(changeEvent.file.status)) {
+			if (changeEvent.file.status === "error") {
+				notifyErrorHandler("Error uploading file")(changeEvent.file.error);
+			}
+
+			let newUploadingFiles = [...uploadingFiles];
+			let index = newUploadingFiles.findIndex(f => f.uid === changeEvent.file.uid);
+			if (index !== -1) {
+				newUploadingFiles.splice(index, 1);
+				setUploadingFiles(newUploadingFiles);
+			}
+			return;
+		}
+
+		let file = {
+			uid: changeEvent.file.uid,
+			name: changeEvent.file.name,
+			percent: changeEvent.file.percent,
+			status: changeEvent.file.status,
+		};
+
+		let newUploadingFiles = [...uploadingFiles];
+		let index = newUploadingFiles.findIndex(f => f.uid === changeEvent.file.uid);
+		if (index !== -1) {
+			newUploadingFiles[index] = file;
+		} else {
+			newUploadingFiles.push(file);
+		}
+		setUploadingFiles(newUploadingFiles);
+	}
+
 	let uploadProps = {
 		name: "file",
 		accept: ".zip",
@@ -118,7 +151,7 @@ export default function SavesList(props) {
 		},
 		showUploadList: false,
 		action: `${webRoot}api/upload-save`,
-		// TODO: show progress to user.
+		onChange,
 	};
 
 	return <div>
@@ -131,5 +164,15 @@ export default function SavesList(props) {
 		<Upload.Dragger className="save-list-dragger" openFileDialogOnClick={false} {...uploadProps}>
 			{saveTable}
 		</Upload.Dragger>
+		{uploadingFiles.length ? <List>
+			{uploadingFiles.map(file => <List.Item key={file.uid}>
+				{file.name}
+				<Progress
+					percent={file.percent}
+					format={percent => `${Math.floor(percent)}%`}
+					status={file.status === "error" ? "exception" : "normal"}
+				/>
+			</List.Item>)}
+		</List> : null}
 	</div>;
 }
diff --git a/test/integration/clusterio.js b/test/integration/clusterio.js
index 5f3d6441..fff1c043 100644
--- a/test/integration/clusterio.js
+++ b/test/integration/clusterio.js
@@ -65,6 +65,12 @@ describe("Integration of Clusterio", function() {
 	describe("clusterioslave", function() {
 		describe("slaveUpdateEventHandler()", function() {
 			it("should trigger when a new slave is added", async function() {
+				// On windows there's currently no way to automate graceful shutdown of the slave
+				// process as CTRL+C is some weird terminal thing and SIGINT isn't a thing.
+				if (process.platform === "win32") {
+					this.skip();
+				}
+
 				slowTest(this);
 				getControl().slaveUpdates = [];
 				let config = "alt-slave-config.json";
diff --git a/test/master/routes.js b/test/master/routes.js
index 7037be75..cca2c3b7 100644
--- a/test/master/routes.js
+++ b/test/master/routes.js
@@ -325,5 +325,25 @@ describe("master/src/routes", function() {
 			assert.deepEqual(JSON.parse(response.body), { saves: ["test.zip"] });
 			assert.equal(response.statusCode, 200);
 		});
+		it("should complete a valid transfer with non-standerd mime type", async function() {
+			master.forwardRequestToInstance = async (request, data) => {
+				let stream = await phin({
+					url: `http://localhost:${port}/api/stream/${data.stream_id}`,
+				});
+				assert.equal(stream.body.toString(), "totally a zip file");
+				return { save: data.filename };
+			};
+			let response;
+			response = await phin({
+				url: `http://localhost:${port}/api/upload-save?instance_id=123&filename=test.zip`, method: "POST",
+				headers: {
+					"X-Access-Token": testToken,
+					"Content-Type": "application/x-zip-compressed",
+				},
+				data: "totally a zip file",
+			});
+			assert.deepEqual(JSON.parse(response.body), { saves: ["test.zip"] });
+			assert.equal(response.statusCode, 200);
+		});
 	});
 });