Unnotifier solved my problems

I was using the more popular plugin to disable admin notices individually and premium. Suddenly, all my WordPress sites were crashing when trying to log into the backend. Not only did the other plugin cause my sites to crash (which on top of all that, I had to pay for the premium version), but I used to always get warnings about it being insecure. Well, now it’s garbage and Unnotifier seems to being a great job of handling the task.