Issue #15587: Enable Tk high-resolution text rendering on Macs with
Retina displays.  Applies to Tkinter apps, such as IDLE, on OS X
framework builds linked with Cocoa Tk 8.5+.
Suggested by Kevin Walzer
diff --git a/Mac/IDLE/Info.plist.in b/Mac/IDLE/Info.plist.in
index dc09be8..71ff0ff 100644
--- a/Mac/IDLE/Info.plist.in
+++ b/Mac/IDLE/Info.plist.in
@@ -51,6 +51,8 @@
 	<string>%VERSION%</string>
 	<key>CFBundleVersion</key>
 	<string>%VERSION%</string>
+	<key>NSHighResolutionCapable</key>
+	<true/>
 <!--
 	<key>LSMinimumSystemVersionByArchitecture</key>
 	<dict>
diff --git a/Mac/Resources/app/Info.plist.in b/Mac/Resources/app/Info.plist.in
index a91b1ee..8af5efc 100644
--- a/Mac/Resources/app/Info.plist.in
+++ b/Mac/Resources/app/Info.plist.in
@@ -56,5 +56,7 @@
 	<true/>
 	<key>NSHumanReadableCopyright</key>
 	<string>(c) 2013 Python Software Foundation.</string>
+	<key>NSHighResolutionCapable</key>
+	<true/>
 </dict>
 </plist>
diff --git a/Misc/NEWS b/Misc/NEWS
index 591aad1..fb68dde 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -800,6 +800,10 @@
 
 - Issue #14437: Fix building the _io module under Cygwin.
 
+- Issue #15587: Enable Tk high-resolution text rendering on Macs with
+  Retina displays.  Applies to Tkinter apps, such as IDLE, on OS X
+  framework builds linked with Cocoa Tk 8.5.
+
 Tools/Demos
 -----------