diff --git a/flatpak/io.github.TTimo.GtkRadiant.appdata.xml b/flatpak/io.github.TTimo.GtkRadiant.appdata.xml
new file mode 100644
index 00000000..6df918de
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+++ b/flatpak/io.github.TTimo.GtkRadiant.appdata.xml
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+<?xml version="1.0" encoding="UTF-8"?>
+<component type="desktop-application">
+  <id>io.github.TTimo.GtkRadiant</id>
+  <name>GtkRadiant</name>
+  <content_rating type="oars-1.1" />
+  <summary>Level editor for ID Tech based games including Quake series</summary>
+  <developer_name>Timothee "TTimo" Besset</developer_name>
+  <url type="homepage">https://icculus.org/gtkradiant/</url>
+  <url type="bugtracker">https://github.com/TTimo/GtkRadiant/issues</url>
+  <url type="help">https://icculus.org/gtkradiant/documentation.html</url>
+  <categories>
+    <category>Development</category>
+    <category>X-LevelEditor</category>
+    <category>X-GameLevelEditor</category>
+  </categories>
+  <description>
+    <p>
+      GtkRadiant is the official level design toolchain for games powered by id Tech engines from id Software, and is maintained by a community of volunteers. GtkRadiant is powered by the GTK+ Project and released under a GPL license.
+    </p>
+  </description>
+  <project_license>GPL-2.0</project_license>
+  <metadata_license>CC0-1.0</metadata_license>
+  <screenshots>
+    <screenshot type="default">
+      <caption>GtkRadiant. Level design tools</caption>
+      <image type="source" width="897" height="432">https://icculus.org/gtkradiant/branding/radiant_v3.svg</image>
+    </screenshot>
+  </screenshots>
+  <releases>
+    <release version="1.6.7" date="2022-12-04">
+      <description>
+        <ul>
+          <li>Flathub availability.</li>
+        </ul>
+      </description>
+    </release>
+    <release version="1.6.6" date="2018-02-03">
+      <description>
+        <ul>
+          <li>Added support for Quake 1.</li>
+          <li>Various bug fixes.</li>
+        </ul>
+      </description>
+    </release>
+    <release version="1.6.5" date="2015-11-08">
+      <description>
+        <ul>
+          <li>Added support for Unvanquished.</li>
+          <li>Various bug fixes.</li>
+        </ul>
+      </description>
+    </release>
+    <release version="1.6.4" date="2013-07-25">
+      <description>
+        <ul>
+          <li>MacOS X support and official binaries available.</li>
+          <li>Added support for Quake2World [1] and vanilla Quake2.</li>
+          <li>Added support for Return to Castle Wolfenstein.</li>
+          <li>Added Star Trek Voyage: Elite Force game pack.</li>
+          <li>Added Jedi Academy gamepack.</li>
+          <li>Project codebase updated to Visual Studio 2012 on Windows, including all supporting libraries (gtk, jpeg, libxml).</li>
+          <li>On Windows, choice of 32 bit q3map2 or 64 bit q3map2. Note that the editor itself is still a 32 bit application.</li>
+          <li>Added -exportents option to q3map2 and q3map2_urt: some idTech3 games can load entities from a separate file than the .bsp.</li>
+          <li>Increased the max textures directory limit.</li>
+          <li>Added support for multiple vertex selection and drag.</li>
+          <li>Added a toolbar button to toggle creating detail brushes or structural brushes by default.</li>
+          <li>Added a preference option to create all brushes with a caulk texture.</li>
+          <li>Numerous fixes to the 4-view layout, in particular to the floating dialog window that works with it.</li>
+          <li>idTech3 surface inspector was redone and simplified.</li>
+          <li>Improved GL font rendering on Windows.</li>
+          <li>A lot of code cleanups.</li>
+        </ul>
+      </description>
+    </release>
+  </releases>
+</component>
diff --git a/flatpak/io.github.TTimo.GtkRadiant.desktop b/flatpak/io.github.TTimo.GtkRadiant.desktop
new file mode 100644
index 00000000..6ff5273a
--- /dev/null
+++ b/flatpak/io.github.TTimo.GtkRadiant.desktop
@@ -0,0 +1,12 @@
+[Desktop Entry]
+Version=1.0
+Name=GtkRadiant
+GenericName=GtkRadiant
+Type=Application
+Comment=Level editor for ID Tech based games including Quake series.
+Icon=io.github.TTimo.GtkRadiant
+Exec=gtkradiant
+Terminal=false
+StartupNotify=false
+Keywords=multi;engine;level editor;quake;id tech;
+Categories=Development;X-LevelEditor;X-GameLevelEditor;