From 2fdeb4eafa2e56c0fd398cd7ac41ff8d2d476363 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Thu, 29 Oct 2020 16:57:32 -0700
Subject: [PATCH 1/2] Do not scroll when closing the menu with space

Fixes #1082
---
 static/menu.js | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/static/menu.js b/static/menu.js
index 87e116a6e..fd8328187 100644
--- a/static/menu.js
+++ b/static/menu.js
@@ -128,14 +128,25 @@
                     break;
                 case "enter":
                 case "return":
+                    // enter and return have the default browser behavior,
+                    // but they also close the menu
+                    // this behavior is identical between both the WAI example, and GitHub's
+                    setTimeout(function() {
+                        closeMenu();
+                    }, 100);
+                    break;
                 case "space":
                 case " ":
-                    // enter, return, and space have the default browser behavior,
-                    // but they also close the menu
+                    // space closes the menu, and activates the current link
                     // this behavior is identical between both the WAI example, and GitHub's
+                    if (document.activeElement instanceof HTMLAnchorElement && !document.activeElement.hasAttribute("aria-haspopup")) {
+                        document.activeElement.click();
+                    }
                     setTimeout(function() {
                         closeMenu();
                     }, 100);
+                    e.preventDefault();
+                    e.stopPropagation();
                     break;
                 case "home":
                 case "pageup":

From 6d51510f73df78a174e665f8b23576707512da06 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Thu, 29 Oct 2020 18:12:12 -0700
Subject: [PATCH 2/2] Add descriptive comment for the space behaviour

---
 static/menu.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/static/menu.js b/static/menu.js
index fd8328187..6ad05f9d6 100644
--- a/static/menu.js
+++ b/static/menu.js
@@ -140,6 +140,28 @@
                     // space closes the menu, and activates the current link
                     // this behavior is identical between both the WAI example, and GitHub's
                     if (document.activeElement instanceof HTMLAnchorElement && !document.activeElement.hasAttribute("aria-haspopup")) {
+                        // It's supposed to copy the behaviour of the WAI Menu Bar
+                        // page, and of GitHub's menus. I've been using these two
+                        // sources to judge what is basically "industry standard"
+                        // behaviour for menu keyboard activity on the web.
+                        //
+                        // On GitHub, here's what I notice:
+                        //
+                        // 1 If you click open a menu, the menu button remains
+                        //   focused. If, in this stage, I press space, the menu will
+                        //   close.
+                        //
+                        // 2 If I use the arrow keys to focus a menu item, and then
+                        //   press space, the menu item will be activated. For
+                        //   example, clicking "+", then pressing down, then pressing
+                        //   space will open the New Repository page.
+                        //
+                        // Behaviour 1 is why the
+                        // `!document.activeElement.hasAttribute("aria-haspopup")`
+                        // condition is there. It's to make sure the menu-link on
+                        // things like the About dropdown don't get activated.
+                        // Behaviour 2 is why this code is required at all; I want to
+                        // activate the currently highlighted menu item.
                         document.activeElement.click();
                     }
                     setTimeout(function() {