Add language support (with the Flask-Babel extension)

[Brett Alistair Kromkamp]

See URL: https://python-babel.github.io/flask-babel/

Several users have requested for Contextualise to be translated to their language. In order to do so, proper language support needs to be added to Contextualise.

[Brett Alistair Kromkamp]

See URL: https://pofile.net/free-po-editor

[Gini.mod]

Hello,

Where is the Localisation repository ?
I can work on the french translation