diff --git a/app.py b/app.py
index 09ce6025dff..7d1dcfc62e6 100644
--- a/app.py
+++ b/app.py
@@ -25,7 +25,7 @@
                    redirect, request, send_file, url_for,
                    send_from_directory, session)
 from flask_babel import Babel
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 from website.flask_commonmark import Commonmark
 from flask_compress import Compress
 from urllib.parse import quote_plus
diff --git a/gettext_with_fallback.py b/gettext_with_fallback.py
deleted file mode 100644
index f52740d0d83..00000000000
--- a/gettext_with_fallback.py
+++ /dev/null
@@ -1,8 +0,0 @@
-from flask_babel import gettext
-from website.flask_helpers import gettext_with_fallback
-
-
-# Explicitly substitute the flask_babel function gettext with our own implementation that
-# adds a fallback language. Note that we need to monkey-patch instead of use the gettext_with_fallback
-# directly because the Babel extract function works if we use gettext with literal strings.
-gettext = gettext_with_fallback  # noqa
diff --git a/hedy.py b/hedy.py
index 5afafa91ea4..0411a492138 100644
--- a/hedy.py
+++ b/hedy.py
@@ -2,7 +2,7 @@
 from functools import lru_cache
 
 import lark
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 from lark import Lark
 from lark.exceptions import UnexpectedEOF, UnexpectedCharacters, VisitError
 from lark import Tree, Transformer, visitors, v_args
diff --git a/hedy_error.py b/hedy_error.py
index 8b2f2554945..b1edc32b0e4 100644
--- a/hedy_error.py
+++ b/hedy_error.py
@@ -1,7 +1,7 @@
 import hedy
 import hedy_translation
 import re
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 
 # TODO: we should not maintain a list like this. Translation of exception arguments should happen when the exception
diff --git a/tests/tests_z_yamlfile.py b/tests/tests_z_yamlfile.py
index f280bff2403..8aa96d4f93f 100644
--- a/tests/tests_z_yamlfile.py
+++ b/tests/tests_z_yamlfile.py
@@ -41,3 +41,76 @@ def test_load_yaml_equivalent(self):
         print(
             f'YAML loading takes {original_seconds / n} seconds, unpickling takes {cached_seconds / n}'
             f'({original_seconds / cached_seconds:.1f}x faster)')
+
+    # Merging of YAML content
+    # Key of type dict
+    def test_merge_dicts_prefers_source(self):
+        result = YamlFile.merge_yaml({"key1": "source"}, {"key1": "fallback"})
+        self.assertEqual({"key1": "source"}, result)
+
+    def test_merge_dicts_uses_fallback_if_source_key_not_present(self):
+        result = YamlFile.merge_yaml({}, {"key1": "fallback"})
+        self.assertEqual({"key1": "fallback"}, result)
+
+    def test_merge_dicts_skips_key_if_not_present_in_fallback_empty(self):
+        result = YamlFile.merge_yaml({"key1": "source"}, {})
+        self.assertEqual({}, result)
+
+    def test_merge_dicts_skips_key_if_not_present_in_fallback(self):
+        result = YamlFile.merge_yaml({"key2": "source"}, {"key1": "fallback"})
+        self.assertEqual({"key1": "fallback"}, result)
+
+    # Key of type list
+    def test_merge_lists_prefers_source(self):
+        result = YamlFile.merge_yaml({"key1": ["a", "b"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["a", "b"]}, result)
+
+    def test_merge_lists_skips_key_if_not_present_in_fallback(self):
+        result = YamlFile.merge_yaml({"key1": ["a", "b"]}, {})
+        self.assertEqual({}, result)
+
+    def test_merge_lists_uses_fallback_if_source_key_not_present_empty(self):
+        result = YamlFile.merge_yaml({}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["c", "d"]}, result)
+
+    def test_merge_lists_uses_fallback_if_source_key_not_present(self):
+        result = YamlFile.merge_yaml({"key2": ["a", "b"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["c", "d"]}, result)
+
+    # Elements in list
+    def test_merge_lists_values_prefers_source(self):
+        result = YamlFile.merge_yaml({"key1": [None, "b"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["c", "b"]}, result)
+
+    def test_merge_lists_values_uses_fallback_if_value_is_empty(self):
+        result = YamlFile.merge_yaml({"key1": ["", "b"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["c", "b"]}, result)
+
+    def test_merge_lists_values_prefers_len_of_fallback(self):
+        result = YamlFile.merge_yaml({"key1": ["a", "b", "e"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["a", "b"]}, result)
+
+    def test_merge_lists_values_prefers_source_values(self):
+        result = YamlFile.merge_yaml({"key1": ["a"]}, {"key1": ["c", "d"]})
+        self.assertEqual({"key1": ["a", "d"]}, result)
+
+    # Keys with mismatched types
+    def test_merge_dicts_prefers_fallback_type_dict(self):
+        result = YamlFile.merge_yaml({"key1": ["a", "b"]}, {"key1": {"a": "c", "b": "d"}})
+        self.assertEqual({"key1": {"a": "c", "b": "d"}}, result)
+
+    def test_merge_dicts_prefers_fallback_type_str(self):
+        result = YamlFile.merge_yaml({"key1": ["a", "b"]}, {"key1": "string value"})
+        self.assertEqual({"key1": "string value"}, result)
+
+    def test_merge_dicts_prefers_fallback_type_list(self):
+        result = YamlFile.merge_yaml({"key1": {"a": "c", "b": "d"}}, {"key1": ["a", "b"]})
+        self.assertEqual({"key1": ["a", "b"]}, result)
+
+    def test_merge_dicts_prefers_fallback_type_string(self):
+        result = YamlFile.merge_yaml({"key1": {"a": "c", "b": "d"}}, {"key1": "string value"})
+        self.assertEqual({"key1": "string value"}, result)
+
+    def test_merge_dicts_prefers_fallback_type_bool(self):
+        result = YamlFile.merge_yaml({"key1": True}, {"key1": "string value"})
+        self.assertEqual({"key1": True}, result)
diff --git a/translations/en/LC_MESSAGES/messages.po b/translations/en/LC_MESSAGES/messages.po
index ef2aee4b699..80537726995 100644
--- a/translations/en/LC_MESSAGES/messages.po
+++ b/translations/en/LC_MESSAGES/messages.po
@@ -1577,7 +1577,7 @@ msgid "star"
 msgstr "a star"
 
 msgid "start_learning"
-msgstr "Start learning EN"
+msgstr "Start learning"
 
 msgid "start_quiz"
 msgstr "Start quiz"
diff --git a/utils.py b/utils.py
index 07a13b9b322..661b7ed6505 100644
--- a/utils.py
+++ b/utils.py
@@ -19,7 +19,7 @@
 
 from email_validator import EmailNotValidError, validate_email
 from flask_babel import format_date, format_datetime, format_timedelta
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 from ruamel import yaml
 import commonmark
 
diff --git a/website/admin.py b/website/admin.py
index 55dbf0fa763..22a7822e4cd 100644
--- a/website/admin.py
+++ b/website/admin.py
@@ -1,5 +1,5 @@
 from flask import make_response, request
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 import utils
 from website.flask_helpers import render_template
diff --git a/website/auth.py b/website/auth.py
index 0f3ffa35d88..ca5f5ec9cb7 100644
--- a/website/auth.py
+++ b/website/auth.py
@@ -12,7 +12,7 @@
 from botocore.exceptions import NoCredentialsError
 from flask import g, request, session, redirect
 from flask_babel import force_locale
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 import utils
 from config import config
diff --git a/website/auth_pages.py b/website/auth_pages.py
index ed726596960..d708fdad6d7 100644
--- a/website/auth_pages.py
+++ b/website/auth_pages.py
@@ -1,7 +1,7 @@
 import datetime
 
 from flask import make_response, redirect, request, session
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 from config import config
 from safe_format import safe_format
diff --git a/website/classes.py b/website/classes.py
index 0b90ffb83b8..59487aa3a27 100644
--- a/website/classes.py
+++ b/website/classes.py
@@ -2,7 +2,7 @@
 
 from flask import make_response, redirect, request, session
 from jinja_partials import render_partial
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 import utils
 from config import config
diff --git a/website/feedback.py b/website/feedback.py
index 0caff5ff7ff..42474d3a3a5 100644
--- a/website/feedback.py
+++ b/website/feedback.py
@@ -1,6 +1,6 @@
 
 from flask import request, make_response, render_template
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import json
 import uuid
 from collections import defaultdict
diff --git a/website/for_teachers.py b/website/for_teachers.py
index 04b2ac3d3e4..af808f3e70f 100644
--- a/website/for_teachers.py
+++ b/website/for_teachers.py
@@ -7,7 +7,7 @@
 from bs4 import BeautifulSoup
 from flask import g, make_response, request, session, url_for, redirect
 from jinja_partials import render_partial
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import jinja_partials
 
 import hedy
diff --git a/website/parsons.py b/website/parsons.py
index 4766ea1ba7c..898cf26e9de 100644
--- a/website/parsons.py
+++ b/website/parsons.py
@@ -1,5 +1,5 @@
 from flask import g, make_response
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 from .website_module import WebsiteModule, route
 
diff --git a/website/profile.py b/website/profile.py
index b24f824337a..a68dbd1eadd 100644
--- a/website/profile.py
+++ b/website/profile.py
@@ -3,7 +3,7 @@
 
 import requests
 from flask import make_response, request, session
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 
 from safe_format import safe_format
 from hedy_content import ALL_KEYWORD_LANGUAGES, ALL_LANGUAGES, COUNTRIES
diff --git a/website/programs.py b/website/programs.py
index fe2232d4243..7e93d84ffaf 100644
--- a/website/programs.py
+++ b/website/programs.py
@@ -3,7 +3,7 @@
 from typing import Optional
 
 from flask import g, make_response, request
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import jinja_partials
 import hedy_content
 
diff --git a/website/public_adventures.py b/website/public_adventures.py
index 0f9bf3f0e80..9e19c3d9191 100644
--- a/website/public_adventures.py
+++ b/website/public_adventures.py
@@ -1,6 +1,6 @@
 import uuid
 from flask import g, request, make_response
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import json
 
 import hedy
diff --git a/website/tags.py b/website/tags.py
index e8c7a3c55b2..5c9c9590878 100644
--- a/website/tags.py
+++ b/website/tags.py
@@ -1,5 +1,5 @@
 from flask import make_response, request, g
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import jinja_partials
 import uuid
 
diff --git a/website/user_activity.py b/website/user_activity.py
index 6641117f996..5b5cbd68a03 100644
--- a/website/user_activity.py
+++ b/website/user_activity.py
@@ -1,5 +1,5 @@
 
-from gettext_with_fallback import gettext
+from website.flask_helpers import gettext_with_fallback as gettext
 import os
 from flask import make_response, request, session