Flatpak writes files for installed applications with the full Flatpak (store) path. This patch makes it write just "flatpak", using Flatpak from PATH. This is similar to the NixOS [0] patch, updated for Flatpak 1.12.1

[0] https://github.com/NixOS/nixpkgs/blob/bf4167861d0f864b0fc457778d54feb4a2675ea2/pkgs/development/libraries/flatpak/use-flatpak-from-path.patch

diff --git a/common/flatpak-dir.c b/common/flatpak-dir.c
index 80ff5e5f..0c111c31 100644
--- a/common/flatpak-dir.c
+++ b/common/flatpak-dir.c
@@ -7134,8 +7134,7 @@ export_desktop_file (const char         *app,
         flatpak = FLATPAK_BINDIR "/flatpak";

       g_string_append_printf (new_exec,
-                              "%s run --branch=%s --arch=%s",
-                              flatpak,
+                              "flatpak run --branch=%s --arch=%s",
                               escaped_branch,
                               escaped_arch);

@@ -8467,8 +8466,8 @@ flatpak_dir_deploy (FlatpakDir          *self,
       if ((flatpak = g_getenv ("FLATPAK_BINARY")) == NULL)
         flatpak = FLATPAK_BINDIR "/flatpak";

-      bin_data = g_strdup_printf ("#!/bin/sh\nexec %s run --branch=%s --arch=%s %s \"$@\"\n",
-                                  flatpak, escaped_branch, escaped_arch, escaped_app);
+      bin_data = g_strdup_printf ("#!/bin/sh\nexec flatpak run --branch=%s --arch=%s %s \"$@\"\n",
+                                  escaped_branch, escaped_arch, escaped_app);
       if (!g_file_replace_contents (wrapper, bin_data, strlen (bin_data), NULL, FALSE,
                                     G_FILE_CREATE_REPLACE_DESTINATION, NULL, cancellable, error))
         return FALSE;
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<div class='path'>path: <a href='/guix/log/?id=083c9c73757c97afc1e3cdbeb200c2ab1dc33547'>root</a>/<a href='/guix/log/gnu?id=083c9c73757c97afc1e3cdbeb200c2ab1dc33547'>gnu</a>/<a href='/guix/log/gnu/packages?id=083c9c73757c97afc1e3cdbeb200c2ab1dc33547'>packages</a>/<a href='/guix/log/gnu/packages/ibus.scm?id=083c9c73757c97afc1e3cdbeb200c2ab1dc33547'>ibus.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/ibus.scm?id=083c9c73757c97afc1e3cdbeb200c2ab1dc33547&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2018-09-25 11:20:32 +0200'>2018-09-25</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=932839ff124ff3b0dd3070914fb1c5beec69bf32'>gnu: ibus: Update to 1.5.19.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-05-30 07:42:20 +0200'>2018-05-30</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=b3e23b0216be0144e61f48130b8375bc954609f0'>gnu: ibus-libpinyin: Update to 1.10.0.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-05-30 07:42:19 +0200'>2018-05-30</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=8738c2b3426938f92cf5699e4ef8abf9e1a1ee5e'>gnu: libpinyin: Update to 2.2.0.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-01-29 23:27:53 +0100'>2018-01-29</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=50efd06614ec28e2d0e40bc936e48dec81aeac94'>gnu: libpinyin: Update to 2.1.91.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-01-29 23:27:53 +0100'>2018-01-29</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=1f7a84dcc6e9399b21ad363e71c5deeb8b4277f5'>gnu: ibus: Don't capitalise pinyin.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2017-11-13 10:19:26 +0200'>2017-11-13</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=6b7490b3404bcb3f04689e0eb61ef3b5e65aedde'>gnu: ibus: Update to 1.5.17.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2017-11-13 10:19:26 +0200'>2017-11-13</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=ce12b3115762b672d9b8f3699f9ae57c5c033914'>gnu: ibus: Enable wayland support.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2017-09-24 12:43:24 +0200'>2017-09-24</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=07ad172a2473723cb4480105309015968a759f42'>gnu: ibus-libpinyin: Update to 1.9.2.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2017-09-24 12:43:24 +0200'>2017-09-24</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=b9e9ef44ff487ef9f49b248344687067205cb321'>gnu: libpinyin: Update to 2.1.0.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2017-09-04 00:10:59 -0400'>2017-09-04</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=d10092b849153dc27cfed0a9601fde6c7bdec918'>gnu: Put autoconf-related phases immediately after the 'unpack phase.</a><span class='msg-avail'>...</span></td><td>Kei Kebreau</td></tr>
<tr><td><span title='2017-07-04 00:51:52 +0200'>2017-07-04</span></td><td><a href='/guix/commit/gnu/packages/ibus.scm?id=f88eaccf19154bb675216134b255534701f12e9a'>gnu: ibus: Update to 1.5.16.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>