Use a better redirect mechanic in the proxied settings route

app/users/settings/routes.py

@@ -1,4 +1,4 @@
-from flask import abort, flash, redirect, render_template, url_for
+from flask import abort, flash, g, redirect, render_template, url_for
 from flask_breadcrumbs import register_breadcrumb
 from flask_login import current_user, login_required
 from app import db
@@ -17,12 +17,16 @@ from .forms import (
 @bp.route('/<hashid:user_id>/settings', methods=['GET', 'POST'])
 @register_breadcrumb(bp, '.entity.settings', '<i class="material-icons left">settings</i>Settings', endpoint_arguments_constructor=user_eac)
 @login_required
-def settings(user_id, redirect_location_on_post=None):
+def settings(user_id):
     user = User.query.get_or_404(user_id)
     if not (user == current_user or current_user.is_administrator()):
         abort(403)
-    if redirect_location_on_post is None:
-        redirect_location_on_post = url_for('.settings', user_id=user_id)
+
+    redirect_location_on_post = g.pop(
+        'redirect_location_on_post',
+        url_for('.settings', user_id=user_id)
+    )
+
     update_account_information_form = UpdateAccountInformationForm(user)
     update_profile_information_form = UpdateProfileInformationForm(user)
     update_avatar_form = UpdateAvatarForm()