Fix contributed upstream here:
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=42694.

Index: emacs-26.3/src/xfns.c
===================================================================
--- emacs-26.3.orig/src/xfns.c
+++ emacs-26.3/src/xfns.c
@@ -2533,6 +2533,8 @@ xic_free_xfontset (struct frame *f)
 static XIMStyle
 best_xim_style (XIMStyles *xim)
 {
+  if (xim == NULL) goto out;
+
   int i, j;
   int nr_supported = ARRAYELTS (supported_xim_styles);

@@ -2541,6 +2543,7 @@ best_xim_style (XIMStyles *xim)
       if (supported_xim_styles[i] == xim->supported_styles[j])
	return supported_xim_styles[i];

+ out:
   /* Return the default style.  */
   return XIMPreeditNothing | XIMStatusNothing;
 }
ge='this.form.submit();'>
<option value='koszko' selected='selected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=7c2013dcc9acc7dec5152e0efd8d4eb143ce31b1'>root</a>/<a href='/guix/log/etc?id=7c2013dcc9acc7dec5152e0efd8d4eb143ce31b1'>etc</a>/<a href='/guix/log/etc/disarchive-manifest.scm?id=7c2013dcc9acc7dec5152e0efd8d4eb143ce31b1'>disarchive-manifest.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/etc/disarchive-manifest.scm?id=7c2013dcc9acc7dec5152e0efd8d4eb143ce31b1&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-08-06 23:14:41 +0200'>2022-08-06</span></td><td><a href='/guix/commit/etc/disarchive-manifest.scm?id=eab5366e679c149cf0a5abeb9a196700b171d9da'>disarchive-manifest: Exclude the Chromium tarball.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/disarchive-manifest.scm (disarchive-collection): Exclude
"chromium-" tarballs.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-08-05 15:28:02 +0200'>2022-08-05</span></td><td><a href='/guix/commit/etc/disarchive-manifest.scm?id=6d4a0ccecb58c62a95f7f36fa2f4fa53dd52312e'>disarchive-manifest: Filter out origins without a hash.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/disarchive-manifest.scm (disarchive-collection): Filter out
origins with a phony hash.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-08-05 00:14:29 +0200'>2022-08-05</span></td><td><a href='/guix/commit/etc/disarchive-manifest.scm?id=2acffd56a58c01785ea6ea738b79991c0685d364'>disarchive-manifest: Handle tar.xz archives.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/disarchive-manifest.scm (tarball-origin?): Add ".tar.xz".
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-10-09 01:02:18 +0200'>2021-10-09</span></td><td><a href='/guix/commit/etc/disarchive-manifest.scm?id=2ad1ef844632b7605ad6dd362e947a122a0a3925'>disarchive-manifest: Provide valid 'version' string.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/disarchive-manifest.scm &lt;top level&gt;: Turn 'version' field into a
string.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-09-14 11:50:58 +0200'>2021-09-14</span></td><td><a href='/guix/commit/etc/disarchive-manifest.scm?id=98712c14fe3517a48603a12eb2e64db305a54fe5'>etc: Add 'disarchive-manifest.scm'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/disarchive-manifest.scm: New file.
* Makefile.am (EXTRA_DIST): Add it.
</span></span></td><td>Ludovic Courtès</td></tr>