I am trying to run a web-app locally (forked from here ) . I am using the {% trans %} tag to mark strings to be translated.
The original piece of code was <h3> Personal data</h3>.
However , when I change it to <h3>{% trans "Personal data" %}</h3> , the "Personal data" does not get translated , even though the original text (from the forked repository) in the following line gets translated .
The following screenshot highlights the issue :

When I make any changes to the text between <html> tags, it gets reflected in my local instance. But when I make changes to strings marked with {% trans %} , it does not get translated in my local instance (even though the rest of the original text gets translated) .
Note : Changes made to text without {% trans %} tag are getting reflected in my local instance.

The app is run using docker-compose up
Why does the {% trans %} tag not work on new changes ?