Try running the Avast Emergency Update task, then restarting your computer.
After restart the Avast should identify itself as version 17.7.3660.226. It has an update go game mode, which now restores the original state of tasks once the game mode stops.
It also adds a task to task scheduler each time a game is launched, that will restore your original task states after system reboot (in case of unexpected reboot during gaming). Task is removed when you exit the game mode.
Seems they are handling it now quite well
At least as long as you didn't run any games before the patch, or have manually restored the tasks state the first time after the update.
Not sure if they are able to restore the original state of tasks which were modified before the patch, and of which many users are probably unaware.