diff --git a/sys/apis/input.lua b/sys/apis/input.lua
index 75ee1de..a47213a 100644
--- a/sys/apis/input.lua
+++ b/sys/apis/input.lua
@@ -39,11 +39,11 @@ function input:toCode(ch, code)
 
 	-- the key-up event for alt keys is not generated if the minecraft
 	-- window loses focus
-	--
-	-- if keyboard.state[keys.leftAlt] or keyboard.state[keys.rightAlt] or
-	--    code == keys.leftAlt or code == keys.rightAlt then
-	--   table.insert(result, 'alt')
-	-- end
+
+	 if keyboard.state[keys.leftAlt] or keyboard.state[keys.rightAlt] or
+	    code == keys.leftAlt or code == keys.rightAlt then
+	   table.insert(result, 'alt')
+	end
 
 	if keyboard.state[keys.leftShift] or keyboard.state[keys.rightShift] or
 		 code == keys.leftShift or code == keys.rightShift then
diff --git a/sys/extensions/1.device.lua b/sys/extensions/1.device.lua
index 9196c42..2dbdb91 100644
--- a/sys/extensions/1.device.lua
+++ b/sys/extensions/1.device.lua
@@ -75,21 +75,18 @@ end)
 local modifiers = Util.transpose {
 	keys.leftCtrl,  keys.rightCtrl,
 	keys.leftShift, keys.rightShift,
-	keys.leftAlt,   keys.rightAlt,
+	--keys.leftAlt,   keys.rightAlt,
 }
 
 kernel.hook({ 'key', 'key_up', 'char', 'paste' }, function(event, eventData)
 	local code = eventData[1]
 
-	-- maintain global keyboard state
+	-- maintain global keyboard modifier state
 	if modifiers[code] then
 		if event == 'key' then
 			keyboard.state[code] = true
 		elseif event == 'key_up' then
---			if not keyboard.state[code] then
---			return true -- ensure key ups are only generated if a key down was sent
---		end
-		keyboard.state[code] = nil
+			keyboard.state[code] = nil
 		end
 	end
 
@@ -98,6 +95,7 @@ kernel.hook({ 'key', 'key_up', 'char', 'paste' }, function(event, eventData)
 
 	if hotkey and keyboard.hotkeys[hotkey.code] then
 		keyboard.hotkeys[hotkey.code](event, eventData)
+		return true
 	end
 end)