Some older - but widely used - version of the unity gaming engine has a bug that leads to some games registering keypresses twice.
This was today tested by me on Ubuntu Xenial 16.04 LTS with commit #94c7639
Over the years plenty of spam comments piled up in zyanklee.de’s database (around 2k). Deleting them all manually would have been a massive chore, but lately I found help in the disguise of wp cli (https://wp-cli.org/).
How to backup huge mysql myisam databases with a massive load of tables?
I encountered the backup of database servers that hold on to some hundreds of database schemas with each about one hundred tables while having some hundred gigabytes of data in them as a big problem in mysql servers.