Pass next URL to OAuth

app.py

@@ -115,6 +115,12 @@ def set_url_args(**new_args):
     args = {k: v for k, v in args.items() if v is not None}
     return url_for(request.endpoint, **args)
 
+@app.template_global()
+def current_url():
+    args = request.view_args.copy()
+    args.update(request.args)
+    return url_for(request.endpoint, **args)
+
 @app.before_request
 def init_profile():
     g.profiling = []

templates/item.html

@@ -88,7 +88,7 @@
       <div class="alert alert-info mt-4" role="alert">
         This tool must be connected with Wikidata to work.
       </div>
-        <p><a href="{{ url_for('start_oauth') }}" class="btn btn-primary btn-lg">Connect with Wikidata</a>
+        <p><a href="{{ url_for('start_oauth', next=current_url()) }}" class="btn btn-primary btn-lg">Connect with Wikidata</a>
       {% endif %}
 
       {% if username %}