Question about xscreensaver behaviour

Hi all, :wave:

I just want to ask something about xscreensaver.

The screensaver is set to 10 mins; that´s a good value for my purposes.
Yet I´ve experienced something I cannot really explain:

Sometimes I have text read out to me with a text-to-speech-script I once wrote.
If the reading takes longer than 10 minutes the xscreensaver kicks in.

But: I think it shouldn´t, because every now and then I use the space-key of my keyboard. :thinking:

The background of my action is: I read along the text (e.g. pdf-file) and have to turn over a page.
That I do by applying the space-key of my keyboard.

The bottom line is: there is definitively input (by my keyboard) within the 10 minute time frame.

However: when I use my mouse within the 10 minute time frame xscreensaver doesn´t kick in.
So it´s just the keyboard which seems to be ignored. :thinking:

Curious though:

when xscreensaver is active and I want to get my desktop back it really doesn´t matter whether I use my mouse or the keyboard. Any action is recognized and my desktop is displayed.

Can anyone tell my why that behaviour is :question:

Thanks a lot in advance.

Many greetings.
Rosika :slightly_smiling_face:

P.S.:
I´m using Lubuntu 20.04.3 LTS