diff --git a/.github/workflows/tester.yml b/.github/workflows/tester.yml
index f274e88f..42a3683e 100644
--- a/.github/workflows/tester.yml
+++ b/.github/workflows/tester.yml
@@ -4,9 +4,14 @@ on:
   push:
     branches:
         - master
+        - release/*
+    # path filters are not evaluated for pushes of tags
+    tags:
+      - "*"
     paths:
       - ".github/workflows/tester.yml"
       - "**/*.py"
+      - "dicogis/ui/i18n/*"
       - pyproject.toml
 
   pull_request:
@@ -24,6 +29,9 @@ permissions:
 env:
   GDAL_VERSION: 3.*
   PROJECT_FOLDER: "dicogis"
+  # check translations completeness (tests/test_ui_i18n.py) only on tags and
+  # release/* branches. head_ref is the source branch of a pull request, empty on push
+  DICOGIS_I18N_STRICT: ${{ (startsWith(github.ref, 'refs/tags/') || startsWith(github.ref_name, 'release/') || startsWith(github.head_ref, 'release/')) && 'true' || 'false' }}
 
 jobs:
   test-ubuntu:
diff --git a/docs/development/translation.md b/docs/development/translation.md
index ac716e4b..7926758a 100644
--- a/docs/development/translation.md
+++ b/docs/development/translation.md
@@ -73,11 +73,13 @@ Ubuntu installs those binaries in `/usr/lib/qt6/bin/`, which is not on the `PATH
 1. Check your work:
 
     ```sh
-    pytest tests/test_ui_i18n.py
+    DICOGIS_I18N_STRICT=1 pytest tests/test_ui_i18n.py
     ```
 
     That suite fails, naming the offending strings, when a `self.tr()` string has no translation in a shipped locale, or when a `.qm` is out of date with its `.ts`.
 
+    The completeness check (every `self.tr()` string translated) is skipped unless the `DICOGIS_I18N_STRICT` environment variable is true, because translations are legitimately incomplete while a feature is under development. The CI enables it only on tags and on `release/*` branches (including pull requests opened from one), so a release cannot ship an untranslated interface. The `.qm` freshness check always runs.
+
 ### English is the source language
 
 `dicogis_en.ts` is kept as a reference of the extracted strings and is regenerated like the others, but it is **never translated, compiled nor loaded**: with no translator installed, Qt returns the source string, which is already English. `DicoGIS._install_qt_translator()` accordingly removes any installed translator and returns early for `EN`.
diff --git a/tests/test_ui_i18n.py b/tests/test_ui_i18n.py
index 702d319e..81bebc07 100644
--- a/tests/test_ui_i18n.py
+++ b/tests/test_ui_i18n.py
@@ -22,12 +22,16 @@
 
 # standard library
 import ast
+from os import getenv
 from pathlib import Path
 from xml.etree import ElementTree
 
 # 3rd party
 import pytest
 
+# project
+from dicogis.utils.str2bool import str2bool
+
 
 # ##############################################################################
 # ########## Globals ###############
@@ -39,6 +43,16 @@
 # loaded at runtime, so untranslated entries there are expected
 TRANSLATED_LOCALES = ("fr", "es")
 
+# Missing translations are expected while features are under development, so the
+# completeness check is only enforced when explicitly enabled: the CI does it on
+# tags and `release/*` branches, a contributor can do it locally with
+# `DICOGIS_I18N_STRICT=1 pytest tests/test_ui_i18n.py`
+I18N_STRICT_ENV_VAR = "DICOGIS_I18N_STRICT"
+requires_i18n_strict = pytest.mark.skipif(
+    not str2bool(getenv(I18N_STRICT_ENV_VAR, "False")),
+    reason=f"translations completeness only checked if {I18N_STRICT_ENV_VAR} is true",
+)
+
 
 # ##############################################################################
 # ########## Functions #############
@@ -108,6 +122,7 @@ def test_translatable_sources_are_found() -> None:
     assert len(_translatable_sources()) > 50
 
 
+@requires_i18n_strict
 @pytest.mark.parametrize("locale", TRANSLATED_LOCALES)
 def test_every_widget_string_is_translated(locale: str) -> None:
     """Every `self.tr()` string must have a translation in each shipped locale.