I am uploading a NMU with the debdiff attached.
diff -Nru spek-0.8.5+dfsg/debian/changelog spek-0.8.5+dfsg/debian/changelog
--- spek-0.8.5+dfsg/debian/changelog 2024-07-29 22:58:09.000000000 +0200
+++ spek-0.8.5+dfsg/debian/changelog 2025-01-25 21:06:42.000000000 +0100
@@ -1,3 +1,10 @@
+spek (0.8.5+dfsg-5.1) unstable; urgency=medium
+
+ * Non-maintainer upload.
+ * Enable build with gettext 0.23.1. (Closes: #1092237)
+
+ -- Bastian Germann <b...@debian.org> Sat, 25 Jan 2025 21:06:42 +0100
+
spek (0.8.5+dfsg-5) unstable; urgency=high
* debian/changelog:
diff -Nru spek-0.8.5+dfsg/debian/patches/06_gettext-0.23.patch
spek-0.8.5+dfsg/debian/patches/06_gettext-0.23.patch
--- spek-0.8.5+dfsg/debian/patches/06_gettext-0.23.patch 1970-01-01
01:00:00.000000000 +0100
+++ spek-0.8.5+dfsg/debian/patches/06_gettext-0.23.patch 2025-01-13
01:37:52.000000000 +0100
@@ -0,0 +1,16 @@
+Description: Fix build with gettext 0.23
+Author: Santiago Vila <sanv...@debian.org>
+Bug-Debian: https://bugs.debian.org/1092237
+Last-Update: 2025-01-13
+
+--- a/configure.ac
++++ b/configure.ac
+@@ -68,7 +68,7 @@
+ GETTEXT_PACKAGE=spek
+ AC_DEFINE_UNQUOTED([GETTEXT_PACKAGE], ["$GETTEXT_PACKAGE"], [Gettext Package])
+ AC_SUBST(GETTEXT_PACKAGE)
+-AM_GNU_GETTEXT_VERSION([0.21])
++AM_GNU_GETTEXT_REQUIRE_VERSION([0.21])
+ AM_GNU_GETTEXT([external])
+
+ AC_CONFIG_FILES([
diff -Nru spek-0.8.5+dfsg/debian/patches/series
spek-0.8.5+dfsg/debian/patches/series
--- spek-0.8.5+dfsg/debian/patches/series 2024-07-28 18:51:10.000000000
+0200
+++ spek-0.8.5+dfsg/debian/patches/series 2025-01-25 21:06:24.000000000
+0100
@@ -4,3 +4,4 @@
03_metainfo.patch
04_ftbfs-source-after-build.patch
05_ftbfs-undersized-buff-arm32.patch
+06_gettext-0.23.patch
