The topic says it already.
How can I activate this feature, please?

Too few info

1 members found this post helpful.

Here are the missing details:
I'm running Kodi 18 on BL 4.5.0 (32 bit on one machine and 64 bit on another one).
I also installed the PVR add-on IPTV simple client to be able to watch live TV.
There's video text available within that live TV and when I use the page-up key of my keyboard,
I can toggle between the entire video text page, the zoomed upper half of it or the zoomed lower half of it.
When I use the page-down key, I can toggle between the ordinary background and the transparent one, to watch TV behind the text page.

Now, my keyboard has also a numpad with "Page-up" as a 2nd function of the key 9 and "Page-down" as a 2nd function of the key 3.

I've been looking for a way to access these two keys for many months now, especially when Kodi is running, but no chance so far.
A few days ago, I thought, that maybe, if I get the numpad mouse (moving the mouse pointer by means of the numpad) to work,
I might get access to the wanted two keys as well.

What do you mean access?

It sounds like you can push PgUp & PgDn already with their dedicated keys. But appearantly your function key is broken so you can't use them on your 10-key pad, which I assume is part of the same keyboard. Isn't it easier to push the dedicated buttons anyway?

And how would a mouse emulator program help any of this?

PgUp on numpad 9 and PgDn on numpad 3 are actually not broken, they do work for instance for text editors.

They just don't for Kodi.
I guess, there must be some way to make them work there, too, but I don't now how.

As for the mouse emulator...
Since the numpad can also be used to move the mouse pointer, I think, this should also be true for the two wanted keys.

Is your goal to use your number pad PgUp/PgDn as PgUp/PgDn within kodi under bodhi? If yes, not sure how a number pad mouse emulator would help... but maybe I still don't understand what you want.

You can change key bindings in bodhi, but if they're behaving like you want within bodhi, then it's probably kodi's keymap file you need to play with - https://kodi.wiki/view/Keymap

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