diff --git a/mozregression/cli.py b/mozregression/cli.py
index 8392712df..d67eb6a13 100644
--- a/mozregression/cli.py
+++ b/mozregression/cli.py
@@ -253,7 +253,7 @@ def create_parser(defaults):
     parser.add_argument(
         "--lang",
         metavar="[ar|es-ES|he|ja|zh-CN|...]",
-        help=("build language. Only valid when app is firefox-l10n."),
+        help=("build language. Only valid when app is firefox-l10n or thunderbird-l10n."),
     )
 
     parser.add_argument(
@@ -565,8 +565,10 @@ def validate(self):
             options.app, mozinfo.os, options.bits, mozinfo.processor, options.arch
         )
         if options.lang:
-            if options.app != "firefox-l10n":
-                raise MozRegressionError("--lang is only valid with --app=firefox-l10n")
+            if options.app not in ("firefox-l10n", "thunderbird-l10n"):
+                raise MozRegressionError(
+                    "--lang is only valid with --app=firefox-l10n|thunderbird-l10n"
+                )
             fetch_config.set_lang(options.lang)
         elif options.app == "firefox-l10n":
             raise MozRegressionError("app 'firefox-l10n' requires a --lang argument")
diff --git a/mozregression/fetch_configs.py b/mozregression/fetch_configs.py
index fa91b2042..73373b3f9 100644
--- a/mozregression/fetch_configs.py
+++ b/mozregression/fetch_configs.py
@@ -360,6 +360,12 @@ def _get_nightly_repo(self, date):
             return "comm-central"
 
 
+class ThunderbirdL10nNightlyConfigMixin(ThunderbirdNightlyConfigMixin):
+    has_build_info = False
+    def _get_nightly_repo(self, date):
+        return "comm-central-l10n"
+
+
 class FennecNightlyConfigMixin(NightlyConfigMixin):
     nightly_base_repo_name = "mobile"
 
@@ -589,6 +595,27 @@ class ThunderbirdConfig(
     pass
 
 
+@REGISTRY.register("thunderbird-l10n")
+class ThunderbirdL10nConfig(CommonConfig, ThunderbirdL10nNightlyConfigMixin):
+    app_name = "thunderbird"
+
+    def set_lang(self, lang):
+        LOG.info("setting lang to {}".format(lang))
+        self.lang = lang
+
+    def build_regex(self):
+        return (
+            get_build_regex(
+                "thunderbird",
+                self.os,
+                self.bits,
+                self.processor,
+                platprefix=r".*\." + self.lang + r"\.",
+            )
+            + "$"
+        )
+
+
 @REGISTRY.register("fennec")
 class FennecConfig(CommonConfig, FennecNightlyConfigMixin, FennecIntegrationConfigMixin):
     BUILD_TYPES = ("shippable", "opt", "pgo", "debug")
diff --git a/mozregression/launchers.py b/mozregression/launchers.py
index 735ade008..4a0fee0ca 100644
--- a/mozregression/launchers.py
+++ b/mozregression/launchers.py
@@ -424,6 +424,11 @@ def _install(self, dest):
             self._codesign_sign(self.appdir)
 
 
+@REGISTRY.register("thunderbird-l10n")
+class ThunderbirdL10nLauncher(ThunderbirdLauncher):
+    pass
+
+
 class AndroidLauncher(Launcher):
     app_info = None
     adb = None