`nixos-rebuild switch` causes xserver to stop accepting new connections

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1

I’m not sure when this started, I’m tempted to say- since 19.09 but it seems that I’ve been facing this for about a month now. My nixos-rebuild switch command causes my xserver to stop accepting new connections so I cannot open new windows.

Here’s the only X related part of my config. Would somebody have pointers on first glance?

	services.xserver = {
			enable = true;
			enableCtrlAltBackspace = true;
			displayManager.startx.enable = true;

			# Enable touchpad support.
			libinput={
				enable = true;
				# middleEmulation = true;

				# Needed reboot last time I tried
				# ONLY ONE
				scrollMethod = "button"; #"twofinger" "edge"
				scrollButton = 2;

				# A combination of {button, 2} means middle button
				# can be clicked to scroll, a la, Windows

				accelProfile = "adaptive";
			};


			windowManager.i3 = {
				enable=true;
				extraPackages = [
					pkgs.dmenu
					pkgs.rofi
					pkgs.i3status
					pkgs.j4-dmenu-desktop
					pkgs.slock
					pkgs.xdotool

			];

		};
	};