Per-display scaling factor (and fractional scaling i guess) isn't actually in the display settings

[Vikezor]

What Happened?

Per-display scaling factor was apparently added in #392, which was merged in time for release 8.0.0, but I don't know what to tell you; it just isn't there, and i have enabled the thing

[viktor@big:/etc/nixos]$ gsettings get org.gnome.mutter experimental-features
['scale-monitor-framebuffer']

I'm using NixOS unstable, which has version 8.0.0 of this.

[viktor@big:/etc/nixos]$ nix eval nixpkgs#pantheon.switchboard-plug-display.outPath
"/nix/store/ga1k6b0ssapmf2clcxj113wcsd87bnp2-switchboard-plug-display-8.0.0"

[viktor@big:/etc/nixos]$ ls /nix/store/ga1k6b0ssapmf2clcxj113wcsd87bnp2-switchboard-plug-display-8.0.0
lib  share

here's what it looks like

i wonder if i'm missing something extremely obvious here

Steps to Reproduce

1. open display settings
2. observe that it's still the same as it ever was

Expected Behavior

i don't know what it's supposed to look like in there, but presumably not this

OS Version

Other Linux

Session Type

Secure Session (Wayland)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

No response

[bobby285271]

switchboard-plug-display/src/Widgets/DisplayWidget.vala

Lines 277 to 280 in 0bf6bb9

	if (!MonitorManager.get_default ().global_scale_required) {
	popover_box.append (scale_label);
	popover_box.append (scale_drop_down);
	}

Secure Session (Wayland)

I am looking at meta_monitor_manager_xrandr_get_capabilities, since mutter returns META_MONITOR_MANAGER_CAPABILITY_GLOBAL_SCALE_REQUIRED, I think this is the case here? I haven't packaged Wayland session on NixOS unstable yet :-)