How to use horizontal slider?

General
1

I wonder how the horizontal slider can be used to control for example the volume of TV via IR?

2

With 2.8.1 the slider can be configured but not for IR. If you are in button assignment and click on the slider you get a list of possible commands.

For volume control the device must have a command to set the volume on a specified level and for media streaming a command to set the position. These are (afaik) only possible in IP integrations like AVR (possibly TV with IP integration) and Media Player. There are LG, Samsung and Android TV (Sony, Philips, TCL) IP integrations for TV available.

Ralf