Note some viruses monitor for task manager and will kill themselves if it is opened, then retrigger once it is closed. So if this is happening a lot then may want to look into that

What if task manager also freezes?

Two weeks in switching from Windows to Linux and I never once needed to use the equivalent of Task Manager.

It may well have been beginner’s optimism, but still, it did feel strange, so strange indeed that I started wondering whether Linux Mint even had one and I got promptly reassured in my perception by the fact that instead of being named Task Manager (you act with it), it is named System Monitor (you observe with it).