Bring back don't show again

Hi,

When normally switching on Reading Mode appears a notification explaining some things about Reading Mode.

I put to not show again the notification, if I want the notification again how can I put it again on?

Also

I enabled the screen saver, so far so good.

I received this warning:



I disabled the screen saver and out of curiosity I enabled again and this warning did not showed again, I suppose it have disabled anything, I do not know what.

Does anyone know if something has turned off and if so, what and bring back this warning?

Grateful.