Use appropriate customization groups for newly added modes

exwm-background.el

@@ -34,11 +34,15 @@
 
 (require 'exwm-core)
 
+(defgroup exwm-background nil
+  "Background support."
+  :group 'exwm)
+
 ;;;###autoload
 (define-minor-mode exwm-background-mode
   "Toggle EXWM background support."
   :global t
-  :group 'exwm
+  :group 'exwm-background
   (exwm--global-minor-mode-body background))
 
 (defun exwm-background-enable ()
@@ -51,7 +55,6 @@
   :type '(choice
           (color :tag "Background Color")
           (const :tag "Default" nil))
-  :group 'exwm
   :initialize #'custom-initialize-default
   :set (lambda (symbol value)
          (set-default-toplevel-value symbol value)

exwm-randr.el

@@ -359,7 +359,7 @@ Refresh when any RandR 1.5 monitor changes."
 (define-minor-mode exwm-randr-mode
   "Toggle EXWM randr support."
   :global t
-  :group 'exwm
+  :group 'exwm-randr
   (exwm--global-minor-mode-body randr))
 
 (defun exwm-randr-enable ()

exwm-systemtray.el

@@ -54,7 +54,7 @@
 (define-minor-mode exwm-systemtray-mode
   "Toggle EXWM systemtray support."
   :global t
-  :group 'exwm
+  :group 'exwm-systemtray
   (exwm--global-minor-mode-body systemtray))
 
 (defun exwm-systemtray-enable ()

exwm-xsettings.el

@@ -51,6 +51,10 @@
 (require 'xcb-xsettings)
 (require 'exwm-core)
 
+(defgroup exwm-xsettings nil
+  "XSETTINGS."
+  :group 'exwm)
+
 (defvar exwm-xsettings--connection nil)
 (defvar exwm-xsettings--XSETTINGS_SETTINGS-atom nil)
 (defvar exwm-xsettings--XSETTINGS_S0-atom nil)
@@ -61,7 +65,7 @@
 (define-minor-mode exwm-xsettings-mode
   "Toggle EXWM xsettings support."
   :global t
-  :group 'exwm
+  :group 'exwm-xsettings
   (exwm--global-minor-mode-body xsettings))
 
 (defun exwm-xsettings-enable ()
@@ -80,10 +84,6 @@ SYMBOL is the setting being updated and VALUE is the new value."
   (set-default-toplevel-value symbol value)
   (when exwm-xsettings-mode (exwm-xsettings--update-settings)))
 
-(defgroup exwm-xsettings nil
-  "XSETTINGS."
-  :group 'exwm)
-
 (defcustom exwm-xsettings nil
   "Alist of custom XSETTINGS.
 These settings take precedence over `exwm-xsettings-theme' and