Taken from debian.

# Description: Disable update check by default.
Index: calibre/src/calibre/gui2/main.py
===================================================================
--- calibre.orig/src/calibre/gui2/main.py	2014-02-02 10:41:28.470954623 +0100
+++ calibre/src/calibre/gui2/main.py	2014-02-02 10:41:56.546954247 +0100
@@ -37,8 +37,8 @@
                       help=_('Start minimized to system tray.'))
     parser.add_option('-v', '--verbose', default=0, action='count',
                       help=_('Ignored, do not use. Present only for legacy reasons'))
-    parser.add_option('--no-update-check', default=False, action='store_true',
-            help=_('Do not check for updates'))
+    parser.add_option('--update-check', dest='no_update_check', default=True, action='store_false',
+            help=_('Check for updates'))
     parser.add_option('--ignore-plugins', default=False, action='store_true',
             help=_('Ignore custom plugins, useful if you installed a plugin'
                 ' that is preventing calibre from starting'))
ix/refs/?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>refs</a><a class='active' href='/guix/log/README'>log</a><a href='/guix/tree/README?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>tree</a><a href='/guix/commit/README?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>commit</a><a href='/guix/diff/README?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/README'>
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<div class='path'>path: <a href='/guix/log/?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>root</a>/<a href='/guix/log/README?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9'>README</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/README?id=2365e8435a13c3aa4308e88773de0a0e7b9ffef9&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-05-20 01:58:04 +0200'>2021-05-20</span></td><td><a href='/guix/commit/README?id=c0087d33705f53cc3619a1a43a33602aaecc3a8b'>The #guix channel is hosted by Libera Chat.</a><span class='msg-avail'>...<span class='msg-tooltip'>* README (Contact): Update network name.
* ROADMAP: Likewise.
* doc/contributing.texi (Contributing): Likewise.
* doc/guix.texi (After System Installation): Likewise.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-10-23 12:57:20 -0400'>2020-10-23</span></td><td><a href='/guix/commit/README?id=b5aaa3a4fb985d21e21e2a67f48b52f13ebd4728'>doc: Update README.</a><span class='msg-avail'>...<span class='msg-tooltip'>* README (Installation): Do not mention installing Guix from Git anymore.
(Building from Git): Add section.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2020-10-22 22:47:54 -0400'>2020-10-22</span></td><td><a href='/guix/commit/README?id=503d2bfde08f9bf97bbf430516d2f19faedd4319'>README: Refer to the manual for building from Git.</a><span class='msg-avail'>...<span class='msg-tooltip'>* README (Installing Guix from Guix): Remove section.
(Installation): For installing from Git, refer to the "Building from Git"
section of the manual and suggest using './pre-inst-env guix pull' rather than
'make install' for installing Guix.
</span></span></td><td>Maxim Cournoyer</td></tr>
ip'>Fixes &lt;https://bugs.gnu.org/29761&gt;.
Reported by Martin Castillo &lt;castilma@uni-bremen.de&gt;.

* guix/scripts/gc.scm (argument-&gt;verify-options): New procedure.
(%options) ["verify"]: Adjust to use it.
* tests/guix-gc.sh: Add test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-11-13 10:10:13 +0100'>2017-11-13</span></td><td><a href='/guix/commit/tests/guix-gc.sh?id=ff23b47dbee038236386ddc2ed2fff4c77ad3aa1'>tests: 'guix-gc.sh' passes even when 'out' or 'drv' are defined as env vars.</a><span class='msg-avail'>...<span class='msg-tooltip'>This fixes a test failure exhibited by
fb17a89912c2a3738dae716e30481c11e1c6f0ac whereby assignments to 'out' in
guix-gc.sh would go to the 'out' environment variable, when it exists,
which in turn prevents garbage collection of $out.

* tests/guix-gc.sh: Add 'unset' invocations.
</span></span></td><td>Ludovic Courtès</td></tr>