-Après ajout d'un problème, passer display à "mine"
-Résoudre le pb "no more problems" when navigating after loading one pb
+Use better-sqlite3 instead of node-sqlite3:
+https://www.npmjs.com/package/better-sqlite3
+
+Canvas for hexagonal board Vue reactivity :
+https://stackoverflow.com/questions/40177493/drawing-onto-a-canvas-with-vue-js
+custom directives ?
+
+Desktop notifications:
+https://developer.mozilla.org/fr/docs/Web/API/notification
+
+Think about this:
+https://alligator.io/vuejs/component-communication/
+https://alligator.io/vuejs/global-event-bus/
+
+CRON task remove unlogged users, finished corr games after 7 days, individual challenges older than 7 days