[Milhouse]

Note that for Refresh Rate switching in #0404 and later, it is now necessary to configure the resolutions you want Kodi to use (by default, it won't use any thus no refresh rate switching).

In Settings > Display > Whitelist select the resolutions your TV supports (or you prefer) and then click OK.

May i ask why is that?

The plan is to remove the "Adjust refresh rate" setting and instead use only the Whitelist to configure refresh rate changes - if you don't want any refresh rate changing then don't Whitelist any resolutions/rates. I think once the "Adjust refresh rate" setting is removed then the Whitelist setting should be less confusing, although it's still not as simple as an On/Off/Always/Start&Stop setting but it does give more control over refresh rate selection.

The Whitelist functionality still needs some sort of sensible defaults, maybe a button to set those defaults (ie. enable the desktop resolutions and refresh rates), but for now it's entirely manual. I just enabled all the 1920x1080 resolutions as that's what Kodi outputs to my AVR, and it's working fine for me now, pretty much same as the old "Adjust refresh rate" when set to "Always".

The functionality in the PR continues to be tweaked, so if you have any concerns or suggestions feel free to comment!