diff --git a/devtools/client/aboutdebugging/aboutdebugging.css b/devtools/client/aboutdebugging/aboutdebugging.css
index 78c533d3fbb6..d1116c0d78dd 100644
--- a/devtools/client/aboutdebugging/aboutdebugging.css
+++ b/devtools/client/aboutdebugging/aboutdebugging.css
@@ -101,6 +101,27 @@ button {
   flex-direction: row;
 }
 
+.addons-install-error {
+  background-color: #f3b0b0;
+  padding: 5px 10px;
+  margin: 5px 4px 5px 0px;
+}
+
+.addons-install-error .warning {
+  background-image: url(chrome://devtools/skin/images/alerticon-warning.png);
+  background-size: 13px 12px;
+  margin-right: 10px;
+  display: inline-block;
+  width: 13px;
+  height: 12px;
+}
+
+@media (min-resolution: 1.1dppx) {
+  .addons-install-error .warning {
+    background-image: url(chrome://devtools/skin/images/alerticon-warning@2x.png);
+  }
+}
+
 .addons-options {
   flex: 1;
 }
diff --git a/devtools/client/aboutdebugging/components/addons-controls.js b/devtools/client/aboutdebugging/components/addons-controls.js
index 6ad6f03bf7d2..87f68007add1 100644
--- a/devtools/client/aboutdebugging/components/addons-controls.js
+++ b/devtools/client/aboutdebugging/components/addons-controls.js
@@ -11,10 +11,12 @@ loader.lazyImporter(this, "AddonManager",
   "resource://gre/modules/AddonManager.jsm");
 
 const { Cc, Ci } = require("chrome");
-const { createClass, DOM: dom } =
+const { createFactory, createClass, DOM: dom } =
   require("devtools/client/shared/vendor/react");
 const Services = require("Services");
 
+const AddonsInstallError = createFactory(require("./addons-install-error"));
+
 const Strings = Services.strings.createBundle(
   "chrome://devtools/locale/aboutdebugging.properties");
 
@@ -24,10 +26,17 @@ const MORE_INFO_URL = "https://developer.mozilla.org/docs/Tools" +
 module.exports = createClass({
   displayName: "AddonsControls",
 
+  getInitialState() {
+    return {
+      installError: null,
+    };
+  },
+
   render() {
     let { debugDisabled } = this.props;
 
-    return dom.div({ className: "addons-controls" },
+    return dom.div({ className: "addons-top" },
+      dom.div({ className: "addons-controls" },
         dom.div({ className: "addons-options" },
           dom.input({
             id: "enable-addon-debugging",
@@ -49,7 +58,8 @@ module.exports = createClass({
           id: "load-addon-from-file",
           onClick: this.loadAddonFromFile,
         }, Strings.GetStringFromName("loadTemporaryAddon"))
-      );
+      ),
+      AddonsInstallError({ error: this.state.installError }));
   },
 
   onEnableAddonDebuggingChange(event) {
@@ -59,6 +69,7 @@ module.exports = createClass({
   },
 
   loadAddonFromFile() {
+    this.setState({ installError: null });
     let fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
     fp.init(window,
       Strings.GetStringFromName("selectAddonFromFile2"),
@@ -73,11 +84,10 @@ module.exports = createClass({
     if (!file.isDirectory() && !file.leafName.endsWith(".xpi")) {
       file = file.parent;
     }
-    try {
-      AddonManager.installTemporaryAddon(file);
-    } catch (e) {
-      window.alert("Error while installing the addon:\n" + e.message + "\n");
-      throw e;
-    }
+
+    AddonManager.installTemporaryAddon(file)
+      .catch(e => {
+        this.setState({ installError: e.message });
+      });
   },
 });
diff --git a/devtools/client/aboutdebugging/components/addons-install-error.js b/devtools/client/aboutdebugging/components/addons-install-error.js
new file mode 100644
index 000000000000..a196bbc2524f
--- /dev/null
+++ b/devtools/client/aboutdebugging/components/addons-install-error.js
@@ -0,0 +1,22 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* eslint-env browser */
+"use strict";
+
+const { createClass, DOM: dom } = require("devtools/client/shared/vendor/react");
+
+module.exports = createClass({
+  displayName: "AddonsInstallError",
+
+  render() {
+    if (!this.props.error) {
+      return null;
+    }
+    let text = `There was an error during installation: ${this.props.error}`;
+    return dom.div({ className: "addons-install-error" },
+                   dom.div({ className: "warning" }),
+                   dom.span({}, text));
+  }
+});
diff --git a/devtools/client/aboutdebugging/components/moz.build b/devtools/client/aboutdebugging/components/moz.build
index b41775dee23e..af519f2dd84c 100644
--- a/devtools/client/aboutdebugging/components/moz.build
+++ b/devtools/client/aboutdebugging/components/moz.build
@@ -6,6 +6,7 @@ DevToolsModules(
     'aboutdebugging.js',
     'addon-target.js',
     'addons-controls.js',
+    'addons-install-error.js',
     'addons-tab.js',
     'service-worker-target.js',
     'tab-header.js',
diff --git a/devtools/client/aboutdebugging/test/addons/bad/manifest.json b/devtools/client/aboutdebugging/test/addons/bad/manifest.json
new file mode 100644
index 000000000000..4ab10b4de726
--- /dev/null
+++ b/devtools/client/aboutdebugging/test/addons/bad/manifest.json
@@ -0,0 +1 @@
+this is not valid json
diff --git a/devtools/client/aboutdebugging/test/browser.ini b/devtools/client/aboutdebugging/test/browser.ini
index b2dbd9da60b2..2079f6948185 100644
--- a/devtools/client/aboutdebugging/test/browser.ini
+++ b/devtools/client/aboutdebugging/test/browser.ini
@@ -5,6 +5,7 @@ support-files =
   head.js
   addons/unpacked/bootstrap.js
   addons/unpacked/install.rdf
+  addons/bad/manifest.json
   service-workers/empty-sw.html
   service-workers/empty-sw.js
   service-workers/push-sw.html
diff --git a/devtools/client/aboutdebugging/test/browser_addons_install.js b/devtools/client/aboutdebugging/test/browser_addons_install.js
index 70a8e3a54534..64d236253cb8 100644
--- a/devtools/client/aboutdebugging/test/browser_addons_install.js
+++ b/devtools/client/aboutdebugging/test/browser_addons_install.js
@@ -28,3 +28,30 @@ add_task(function* () {
 
   yield closeAboutDebugging(tab);
 });
+
+add_task(function* () {
+  let { tab, document } = yield openAboutDebugging("addons");
+
+  // Start an observer that looks for the install error before
+  // actually doing the install
+  let top = document.querySelector(".addons-top");
+  let promise = waitForMutation(top, { childList: true });
+
+  // Mock the file picker to select a test addon
+  let MockFilePicker = SpecialPowers.MockFilePicker;
+  MockFilePicker.init(null);
+  let file = getSupportsFile("addons/bad/manifest.json");
+  MockFilePicker.returnFiles = [file.file];
+
+  // Trigger the file picker by clicking on the button
+  document.getElementById("load-addon-from-file").click();
+
+  // Now wait for the install error to appear.
+  yield promise;
+
+  // And check that it really is there.
+  let err = document.querySelector(".addons-install-error");
+  isnot(err, null, "Addon install error message appeared");
+
+  yield closeAboutDebugging(tab);
+});