diff --git a/setup.sh b/setup.sh
index e794504..633a9c0 100644
--- a/setup.sh
+++ b/setup.sh
@@ -197,15 +197,21 @@ logging.basicConfig()
 app = Flask(__name__)
 
 # Load Languages
+import json
+
 TRANSLATIONS = {}
-for lang in app.config['SUPPORTED_LANGUAGES'].split(','):
+SUPPORTED_LANGUAGES = os.getenv('SUPPORTED_LANGUAGES', 'en').split(',')
+
+for lang in SUPPORTED_LANGUAGES:
     try:
-        with open(f'translations/{lang}.json') as f:
+        with open(f'translations/{lang}.json', encoding='utf-8') as f:
             TRANSLATIONS[lang] = json.load(f)
-    except:
+    except Exception:
         TRANSLATIONS[lang] = {}
 
-def translate(key, lang=app.config['DEFAULT_LANGUAGE'], **kwargs):
+def translate(key, lang=None, **kwargs):
+    if not lang:
+        lang = session.get('lang', os.getenv('DEFAULT_LANGUAGE', 'en'))
     return TRANSLATIONS.get(lang, {}).get(key, key).format(**kwargs)
 
 csrf = CSRFProtect(app)
@@ -261,15 +267,13 @@ def enforce_https():
             return redirect(url, code=301)
 
 @app.context_processor
-def inject_translations():
-    def _(key, **kwargs):
-        lang = session.get('lang', app.config['DEFAULT_LANGUAGE'])
-        return translate(key, lang, **kwargs)
-    return {'_': _}
-
 def inject_template_vars():
+    def _(key, **kwargs):
+        lang = session.get('lang', os.getenv('DEFAULT_LANGUAGE', 'en'))
+        return translate(key, lang, **kwargs)
     return dict(
-        get_locale=get_locale,
+        _=_,
+        get_locale=lambda: session.get('lang', os.getenv('DEFAULT_LANGUAGE', 'en')),
         theme='dark' if request.cookies.get('dark_mode') == 'true' else 'light'
     )
 
@@ -338,10 +342,10 @@ def index():
 
 @app.route('/set-lang/<lang>')
 def set_lang(lang):
-    if lang in app.config['SUPPORTED_LANGUAGES'].split(','):
+    if lang in SUPPORTED_LANGUAGES:
         session['lang'] = lang
-    return redirect(request.referrer)
-
+    return redirect(request.referrer or url_for('index'))
+    
 @app.route('/set-theme/<theme>')
 def set_theme(theme):
     resp = make_response('', 204)