Switch completely to Gio for icons and it fixed the startup/lookup time for icons. Now works with every icon theme. Taglist/Tasklist/Window switcher still rely on WM_CLASS and WM_NAME to match the icon name, this probably can't be fixed in a sane way

awesome/rc.lua

@@ -9,7 +9,7 @@
 -- Initialising, order is important!
 require("src.theme.user_config")
 require("src.theme.theme_config")
-require("src.tools.icon_theme")
+require("src.tools.gio_icon_lookup")
 require("src.theme.init")
 require("src.core.error_handling")
 require("src.core.signals")
@@ -20,5 +20,5 @@ require("src.bindings.bind_to_tags")
 require("src.modules.init")
 require("src.tools.helpers.init")
 require("src.tools.hex_to_rgba")
-require("src.tools.auto_starter")(User_config.autostart)
+--require("src.tools.auto_starter")(User_config.autostart)
 require("src.tools.dbus.bluetooth_dbus")()

awesome/src/modules/application_launcher/application.lua

@@ -48,8 +48,6 @@ return function()
                   { -- Icon
                     valign = "center",
                     halign = "center",
-                    --[[ image = xdg_icon_lookup:find_icon(Gio.DesktopAppInfo.get_string(desktop_app_info, "Icon"), 64) or
-                        awful.util.getdir("config") .. "src/assets/icons/fallback.svg", -- fallback icon ]]
                     image = Get_gicon_path(app_info.get_icon(app)),
                     resize = true,
                     widget = wibox.widget.imagebox

awesome/src/modules/crylia_bar/dock.lua

@@ -4,11 +4,10 @@
 -- Awesome Libs
 local awful = require("awful")
 local dpi = require("beautiful").xresources.apply_dpi
+local Gio = require("lgi").Gio
 local gears = require("gears")
 local wibox = require("wibox")
 
-local desktop_parser = require("src.tools.desktop_parser")
-
 return function(screen, programs)
 
   local function create_dock_element(program, size)
@@ -16,6 +15,15 @@ return function(screen, programs)
       return
     end
 
+    local desktop_app_info = Gio.DesktopAppInfo.new_from_filename(program)
+    if not desktop_app_info then
+      return
+    end
+    local gicon = Gio.Icon.new_for_string(Gio.DesktopAppInfo.get_string(desktop_app_info, "Icon"))
+    if not gicon then
+      return
+    end
+
     local dock_element = wibox.widget {
       {
         {
@@ -23,6 +31,7 @@ return function(screen, programs)
             {
               resize = true,
               widget = wibox.widget.imagebox,
+              image = Get_gicon_path(gicon) or "",
               valign = "center",
               halign = "center",
               id = "icon",
@@ -50,8 +59,6 @@ return function(screen, programs)
       widget = wibox.container.margin
     }
 
-    dock_element.background.margin.icon_container.icon.image = xdg_icon_lookup:find_icon(program["Icon"], 64)
-
     for _, c in ipairs(client.get()) do
       if string.lower(c.class):match(program["Icon"]) and c == client.focus then
         dock_element.background.bg = Theme_config.dock.element_focused_bg
@@ -71,7 +78,7 @@ return function(screen, programs)
 
     awful.tooltip {
       objects = { dock_element },
-      text = program["Name"],
+      text = Gio.DesktopAppInfo.get_string(desktop_app_info, "Name"),
       mode = "outside",
       preferred_alignments = "middle",
       margins = dpi(10)
@@ -110,7 +117,7 @@ return function(screen, programs)
     local dock_elements = { layout = wibox.layout.fixed.horizontal }
 
     for i, p in ipairs(pr) do
-      dock_elements[i] = create_dock_element(desktop_parser.Get_desktop_values(p), User_config.dock_icon_size)
+      dock_elements[i] = create_dock_element(Get_desktop_values(p), User_config.dock_icon_size)
     end
 
     return dock_elements
@@ -140,7 +147,7 @@ return function(screen, programs)
       local indicators = { layout = wibox.layout.flex.horizontal, spacing = dpi(5) }
       local col = Theme_config.dock.indicator_bg
       for i, c in ipairs(clients) do
-        local icon = desktop_parser.Get_desktop_values(pr)
+        local icon = Get_desktop_values(pr)
         if icon then
           local icon_name = string.lower(icon["Icon"] or "")
           if icon_name:match(string.lower(c.class or c.name)) then

awesome/src/modules/crylia_bar/init.lua

@@ -3,8 +3,6 @@
 --------------------------------------------------------------------------------------------------------------
 
 return function(s)
-  xdg_icon_lookup = require("src.tools.xdg_icon_lookup")()
-
   ---Lookup function to return the widget from its easy name string
   ---@param widgets table
   ---@return widget

awesome/src/modules/window_switcher/window_elements.lua

@@ -47,7 +47,7 @@ return function()
                 {
                   id = "icon",
                   --!ADD FALLBACK ICON!--
-                  image = xdg_icon_lookup:find_icon(client.class, 64) or client.icon,
+                  image = Get_icon(client.class, client.name) or client.icon,
                   valign = "center",
                   halign = "center",
                   widget = wibox.widget.imagebox

awesome/src/tools/gio_icon_lookup.lua

@@ -0,0 +1,83 @@
+-- Libraries
+local lgi = require("lgi")
+local Gtk = lgi.require("Gtk", "3.0")
+local Gio = lgi.Gio
+local gears = require("gears")
+local GLib = require("lgi").GLib
+
+-- Get all .desktop files as gobjects
+local app_info = Gio.AppInfo
+local app_list = app_info.get_all()
+
+-- Init a new Gtk theme from the users string
+local gtk_theme = Gtk.IconTheme.new()
+Gtk.IconTheme.set_custom_theme(gtk_theme, User_config.icon_theme)
+
+---Gets the icon path from an AppInfo gicon.
+---@param app Gio.AppInfo
+---@return string path
+function Get_gicon_path(app)
+  local icon_info = gtk_theme:lookup_by_gicon(app, 64, 0)
+  if icon_info then
+    local path = icon_info:get_filename()
+    if path then
+      return path
+    end
+  end
+  return ""
+end
+
+---Takes a class and name string and tries to match it to an icon.
+---@param class string
+---@param name string
+---@return string | nil icon_path
+function Get_icon(class, name)
+  class = string.lower(class) or ""
+  name = string.lower(name) or ""
+  for _, app in ipairs(app_list) do
+    local desktop_app_info = Gio.DesktopAppInfo.new(app_info.get_id(app))
+    local icon_string = Gio.DesktopAppInfo.get_string(desktop_app_info, "Icon")
+    if icon_string then
+      icon_string = string.lower(icon_string)
+      if icon_string:match(class) or class:match(icon_string) then
+        return Get_gicon_path(app_info.get_icon(app))
+      elseif icon_string:match(name) or name:match(icon_string) then
+        return Get_gicon_path(app_info.get_icon(app))
+      end
+    end
+  end
+  return nil
+end
+
+---Will return every $XDG_DATA_DIRS
+---@return table
+local function get_paths()
+  local dirs = {}
+
+  local dir
+  for _, value in ipairs(GLib.get_system_data_dirs()) do
+    dir = GLib.build_filenamev({ value, "applications" })
+    if gears.filesystem.dir_readable(dir) then table.insert(dirs, dir) end
+  end
+
+  dir = GLib.build_filenamev({ GLib.get_user_data_dir(), "applications" })
+  if gears.filesystem.dir_readable(dir) then table.insert(dirs, dir) end
+
+  return dirs
+end
+
+---Returns every .desktop file into a table
+---@param file string .desktop files
+---@return string | nil path
+function Get_desktop_values(file)
+
+  if not file or file == "" then
+    return
+  end
+
+  for _, dir in ipairs(get_paths()) do
+    if gears.filesystem.file_readable(dir .. "/" .. file, "r") then
+      return dir .. "/" .. file
+    end
+  end
+end

awesome/src/widgets/taglist.lua

@@ -82,7 +82,7 @@ local list_update = function(widget, buttons, _, _, objects)
           id = "icon_container",
           {
             id = "icon",
-            image = client.icon,
+            image = Get_icon(client.class, client.name) or client.icon,
             resize = true,
             valign = "center",
             halign = "center",
@@ -95,8 +95,6 @@ local list_update = function(widget, buttons, _, _, objects)
         widget = wibox.container.margin
       }
 
-      icon.icon_container.icon:set_image(xdg_icon_lookup:find_icon(client.class, 64) or client.icon)
-
       tag_widget.container:setup({
         icon,
         strategy = "exact",

awesome/src/widgets/tasklist.lua

@@ -22,7 +22,7 @@ local list_update = function(widget, buttons, label, _, objects)
 								valign = "center",
 								halign = "center",
 								resize = true,
-								image = object.icon,
+								image = Get_icon(object.class, object.name) or object.icon,
 								widget = wibox.widget.imagebox
 							},
 							nil,
@@ -114,8 +114,7 @@ local list_update = function(widget, buttons, label, _, objects)
 			task_widget:set_bg(Theme_config.tasklist.bg)
 			task_widget.container.layout_it.title:set_text('')
 		end
-		task_widget:get_children_by_id("icon")[1]:set_image(xdg_icon_lookup:find_icon(object.class, 64) or
-			object.icon)
+
 		widget:add(task_widget)
 		widget:set_spacing(dpi(6))
 

awesome/wibox/layout/fixed.lua

@@ -23,6 +23,7 @@
 -- @supermodule wibox.widget.base
 ---------------------------------------------------------------------------
 
+---@diagnostic disable-next-line: deprecated
 local unpack = unpack or table.unpack -- luacheck: globals unpack (compatibility with Lua 5.1)
 local base   = require("wibox.widget.base")
 local table  = table