From ef74dddfae07e1ca2d5d132be28d9aa4debf1dd5 Mon Sep 17 00:00:00 2001
From: Ian Flanigan <flan@google.com>
Date: Fri, 4 Jan 2019 00:32:56 +0100
Subject: [PATCH] Match the location of the Alt key to the activated Apple key

Modern browsers set the 'location' property on keyboard events when
the key is located in several places. The ALT key, for example, can be
either on the left or the right side of the keyboard.

This change uses the location to determine which Apple key to
activate, if it is available, and defaults to the old behavior if not.
---
 js/main2e.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/js/main2e.js b/js/main2e.js
index 814973e..643fbcc 100644
--- a/js/main2e.js
+++ b/js/main2e.js
@@ -823,7 +823,11 @@ function _keydown(evt) {
     } else if (evt.keyCode == 91 || evt.keyCode == 93) { // Command
         keyboard.commandKey(true);
     } else if (evt.keyCode == 18) { // Alt
-        keyboard.optionKey(true);
+        if (evt.originalEvent.location == 1) {
+            keyboard.commandKey(true);
+        } else {
+            keyboard.optionKey(true);
+        }
     }
 }
 
@@ -838,7 +842,11 @@ function _keyup(evt) {
     } else if (evt.keyCode == 91 || evt.keyCode == 93) { // Command
         keyboard.commandKey(false);
     } else if (evt.keyCode == 18) { // Alt
-        keyboard.optionKey(false);
+        if (evt.originalEvent.location == 1) {
+            keyboard.commandKey(false);
+        } else {
+            keyboard.optionKey(false);
+        }
     }
 }