add setting for enabling server-side decorations

Previously, this was controllable via the undocumented
ZED_WINDOW_DECORATIONS environment variable (added in #13866).
Using an environment variable for this is inconvenient because it
requires users to set that environment variable somehow before
starting Zed, such as in the .desktop file or persistently in their
shell. Controlling this with a Zed setting is more convenient.

This does not modify the design of the titlebar in any way. It only
moves the existing option from an environment variable to a Zed
setting.

Fixes #14165

Author: Be-ing

assets/settings/default.json

@@ -172,6 +172,16 @@
   //
   // Default: true
   "zoomed_padding": true,
+  // What draws Zed's window decorations (titlebar):
+  // 1. Client application (Zed) draws its own window decorations
+  //    "client"
+  // 2. Display server draws the window decorations. Not supported by GNOME Wayland.
+  //    "server"
+  //
+  // This requires restarting Zed for changes to take effect.
+  //
+  // Default: "client"
+  "window_decorations": "client",
   // Whether to use the system provided dialogs for Open and Save As.
   // When set to false, Zed will use the built-in keyboard-first pickers.
   "use_system_path_prompts": true,

crates/rules_library/src/rules_library.rs

@@ -25,7 +25,7 @@ use ui::{
     Divider, KeyBinding, ListItem, ListItemSpacing, ListSubHeader, Render, Tooltip, prelude::*,
 };
 use util::{ResultExt, TryFutureExt};
-use workspace::{Workspace, client_side_decorations};
+use workspace::{Workspace, WorkspaceSettings, client_side_decorations};
 use zed_actions::assistant::InlineAssist;
 
 use prompt_store::*;
@@ -119,10 +119,9 @@ pub fn open_rules_library(
         cx.update(|cx| {
             let app_id = ReleaseChannel::global(cx).app_id();
             let bounds = Bounds::centered(None, size(px(1024.0), px(768.0)), cx);
-            let window_decorations = match std::env::var("ZED_WINDOW_DECORATIONS") {
-                Ok(val) if val == "server" => gpui::WindowDecorations::Server,
-                Ok(val) if val == "client" => gpui::WindowDecorations::Client,
-                _ => gpui::WindowDecorations::Client,
+            let window_decorations = match WorkspaceSettings::get_global(cx).window_decorations {
+                settings::WindowDecorations::Server => gpui::WindowDecorations::Server,
+                settings::WindowDecorations::Client => gpui::WindowDecorations::Client,
             };
             cx.open_window(
                 WindowOptions {

crates/settings/src/settings_content/workspace.rs

@@ -106,6 +106,9 @@ pub struct WorkspaceSettingsContent {
     ///
     /// Default: true
     pub zoomed_padding: Option<bool>,
+    /// What draws window decorations/titlebar, the client application (Zed) or display server
+    /// Default: client
+    pub window_decorations: Option<WindowDecorations>,
 }
 
 #[skip_serializing_none]
@@ -285,6 +288,16 @@ pub enum BottomDockLayout {
     RightAligned,
 }
 
+#[derive(Copy, Clone, Default, Debug, Serialize, Deserialize, PartialEq, JsonSchema, MergeFrom)]
+#[serde(rename_all = "snake_case")]
+pub enum WindowDecorations {
+    /// Zed draws its own window decorations/titlebar (client-side decoration)
+    #[default]
+    Client,
+    /// Show system's window titlebar (server-side decoration; not supported by GNOME Wayland)
+    Server,
+}
+
 #[derive(
     Copy,
     Clone,

crates/workspace/src/workspace_settings.rs

@@ -33,6 +33,7 @@ pub struct WorkspaceSettings {
     pub close_on_file_delete: bool,
     pub use_system_window_tabs: bool,
     pub zoomed_padding: bool,
+    pub window_decorations: settings::WindowDecorations,
 }
 
 #[derive(Copy, Clone, PartialEq, Debug, Default)]
@@ -107,6 +108,7 @@ impl Settings for WorkspaceSettings {
             close_on_file_delete: workspace.close_on_file_delete.unwrap(),
             use_system_window_tabs: workspace.use_system_window_tabs.unwrap(),
             zoomed_padding: workspace.zoomed_padding.unwrap(),
+            window_decorations: workspace.window_decorations.unwrap(),
         }
     }
 

crates/zed/src/zed.rs

@@ -282,10 +282,9 @@ pub fn build_window_options(display_uuid: Option<Uuid>, cx: &mut App) -> WindowO
             .find(|display| display.uuid().ok() == Some(uuid))
     });
     let app_id = ReleaseChannel::global(cx).app_id();
-    let window_decorations = match std::env::var("ZED_WINDOW_DECORATIONS") {
-        Ok(val) if val == "server" => gpui::WindowDecorations::Server,
-        Ok(val) if val == "client" => gpui::WindowDecorations::Client,
-        _ => gpui::WindowDecorations::Client,
+    let window_decorations = match WorkspaceSettings::get_global(cx).window_decorations {
+        settings::WindowDecorations::Server => gpui::WindowDecorations::Server,
+        settings::WindowDecorations::Client => gpui::WindowDecorations::Client,
     };
 
     let use_system_window_tabs = WorkspaceSettings::get_global(cx).use_system_window_tabs;