diff --git a/Containerfile b/Containerfile
index debf202..018c6ef 100644
--- a/Containerfile
+++ b/Containerfile
@@ -1,4 +1,4 @@
-FROM fedora-minimal:latest
+FROM fedora-minimal:37
 
 RUN microdnf install --assumeyes \
 	python3-flask \
diff --git a/app/qrwebform.py b/app/qrwebform.py
index 0fb75fc..9e49c92 100755
--- a/app/qrwebform.py
+++ b/app/qrwebform.py
@@ -2,7 +2,7 @@
 
 from flask import Flask, render_template, flash, request
 from flask_wtf import FlaskForm
-from wtforms import Form, BooleanField, SubmitField, TextField
+from wtforms import Form, BooleanField, SubmitField, StringField
 from wtforms.validators import DataRequired
 import os
 
@@ -12,7 +12,7 @@ app.config.from_object(__name__)
 app.config['SECRET_KEY'] = os.urandom(40)
 
 class QRForm(FlaskForm):
-    user_data = TextField("Dane:", validators=[DataRequired()])
+    user_data = StringField("Dane:", validators=[DataRequired()])
     trim_spaces = BooleanField("Usuń spacje", default=True)
     submit = SubmitField("Generuj")