diff --git a/hosts/homes/ambroisie@bazin/default.nix b/hosts/homes/ambroisie@bazin/default.nix
index 365b70d..cfeba83 100644
--- a/hosts/homes/ambroisie@bazin/default.nix
+++ b/hosts/homes/ambroisie@bazin/default.nix
@@ -29,6 +29,8 @@
       terminalFeatures = {
         # HTerm uses `xterm-256color` as its `$TERM`, so use that here
         xterm-256color = { };
+        # Terminal app uses `xterm.js`, not HTerm
+        "xterm.js" = { };
       };
     };
 
diff --git a/hosts/homes/ambroisie@mousqueton/default.nix b/hosts/homes/ambroisie@mousqueton/default.nix
index 1383618..b6193c9 100644
--- a/hosts/homes/ambroisie@mousqueton/default.nix
+++ b/hosts/homes/ambroisie@mousqueton/default.nix
@@ -35,6 +35,8 @@
       terminalFeatures = {
         # HTerm uses `xterm-256color` as its `$TERM`, so use that here
         xterm-256color = { };
+        # Terminal app uses `xterm.js`, not HTerm
+        "xterm.js" = { };
       };
     };
   };
diff --git a/hosts/nixos/aramis/home.nix b/hosts/nixos/aramis/home.nix
index e8c99e4..7bf6fe2 100644
--- a/hosts/nixos/aramis/home.nix
+++ b/hosts/nixos/aramis/home.nix
@@ -25,7 +25,7 @@
     # Network-Manager applet
     nm-applet.enable = true;
     # Terminal
-    terminal.program = "alacritty";
+    terminal.default = "alacritty";
     # Transmission remote
     trgui.enable = true;
     # Zathura document viewer
diff --git a/modules/home/firefox/tridactyl/default.nix b/modules/home/firefox/tridactyl/default.nix
index 26ddfad..cd377e5 100644
--- a/modules/home/firefox/tridactyl/default.nix
+++ b/modules/home/firefox/tridactyl/default.nix
@@ -2,7 +2,7 @@
 let
   cfg = config.my.home.firefox.tridactyl;
 
-  term = config.my.home.terminal.program;
+  term = config.my.home.terminal.default;
 
   vimCommandLine = {
     alacritty = ''-e "vim" "%f" "+normal!%lGzv%c|"'';
diff --git a/modules/home/terminal/alacritty/default.nix b/modules/home/terminal/alacritty/default.nix
index daf3e80..7d3e1d8 100644
--- a/modules/home/terminal/alacritty/default.nix
+++ b/modules/home/terminal/alacritty/default.nix
@@ -1,9 +1,16 @@
 { config, lib, ... }:
 let
-  cfg = config.my.home.terminal;
+  cfg = config.my.home.terminal.alacritty;
+  inherit (config.my.home.terminal) colors;
 in
 {
-  config = lib.mkIf (cfg.program == "alacritty") {
+  options.my.home.terminal.alacritty = with lib; {
+    enable = lib.mkEnableOption "alacritty" // {
+      default = config.my.home.terminal.default == "alacritty";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
     programs.alacritty = {
       enable = true;
 
@@ -14,36 +21,36 @@ in
 
         colors = {
           primary = {
-            background = cfg.colors.background;
-            foreground = cfg.colors.foreground;
+            background = colors.background;
+            foreground = colors.foreground;
 
-            bright_foreground = cfg.colors.foregroundBold;
+            bright_foreground = colors.foregroundBold;
           };
 
           cursor = {
-            cursor = cfg.colors.cursor;
+            cursor = colors.cursor;
           };
 
           normal = {
-            black = cfg.colors.black;
-            red = cfg.colors.red;
-            green = cfg.colors.green;
-            yellow = cfg.colors.yellow;
-            blue = cfg.colors.blue;
-            magenta = cfg.colors.magenta;
-            cyan = cfg.colors.cyan;
-            white = cfg.colors.white;
+            black = colors.black;
+            red = colors.red;
+            green = colors.green;
+            yellow = colors.yellow;
+            blue = colors.blue;
+            magenta = colors.magenta;
+            cyan = colors.cyan;
+            white = colors.white;
           };
 
           bright = {
-            black = cfg.colors.blackBold;
-            red = cfg.colors.redBold;
-            green = cfg.colors.greenBold;
-            yellow = cfg.colors.yellowBold;
-            blue = cfg.colors.blueBold;
-            magenta = cfg.colors.magentaBold;
-            cyan = cfg.colors.cyanBold;
-            white = cfg.colors.whiteBold;
+            black = colors.blackBold;
+            red = colors.redBold;
+            green = colors.greenBold;
+            yellow = colors.yellowBold;
+            blue = colors.blueBold;
+            magenta = colors.magentaBold;
+            cyan = colors.cyanBold;
+            white = colors.whiteBold;
           };
         };
       };
diff --git a/modules/home/terminal/default.nix b/modules/home/terminal/default.nix
index 20f36b5..72694d2 100644
--- a/modules/home/terminal/default.nix
+++ b/modules/home/terminal/default.nix
@@ -16,11 +16,11 @@ in
 
   options.my.home = with lib; {
     terminal = {
-      program = mkOption {
+      default = mkOption {
         type = with types; nullOr (enum [ "alacritty" "termite" ]);
         default = null;
         example = "termite";
-        description = "Which terminal to use for home session";
+        description = "Which default terminal to use for home session";
       };
 
       colors = {
@@ -56,7 +56,7 @@ in
     };
   };
 
-  config.home.sessionVariables = lib.mkIf (cfg.program != null) {
-    TERMINAL = cfg.program;
+  config.home.sessionVariables = lib.mkIf (cfg.default != null) {
+    TERMINAL = cfg.default;
   };
 }
diff --git a/modules/home/terminal/termite/default.nix b/modules/home/terminal/termite/default.nix
index e8f67a7..f130029 100644
--- a/modules/home/terminal/termite/default.nix
+++ b/modules/home/terminal/termite/default.nix
@@ -1,9 +1,16 @@
 { config, lib, pkgs, ... }:
 let
-  cfg = config.my.home.terminal;
+  cfg = config.my.home.terminal.termite;
+  inherit (config.my.home.terminal) colors;
 in
 {
-  config = lib.mkIf (cfg.program == "termite") {
+  options.my.home.terminal.termite = with lib; {
+    enable = lib.mkEnableOption "termite" // {
+      default = config.my.home.terminal.default == "termite";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
     programs.termite = {
       enable = true;
 
@@ -24,11 +31,11 @@ in
 
 
       # Colors
-      backgroundColor = cfg.colors.background;
-      cursorColor = cfg.colors.cursor;
-      foregroundColor = cfg.colors.foreground;
-      foregroundBoldColor = cfg.colors.foregroundBold;
-      colorsExtra = with cfg.colors; ''
+      backgroundColor = colors.background;
+      cursorColor = colors.cursor;
+      foregroundColor = colors.foreground;
+      foregroundBoldColor = colors.foregroundBold;
+      colorsExtra = with colors; ''
         # Normal colors
         color0 = ${black}
         color1 = ${red}
diff --git a/modules/home/tmux/default.nix b/modules/home/tmux/default.nix
index e3e3daf..6a4d371 100644
--- a/modules/home/tmux/default.nix
+++ b/modules/home/tmux/default.nix
@@ -6,13 +6,16 @@ let
     (config.my.home.wm.windowManager != null)
   ];
 
-  mkTerminalFeature = opt: flag:
+  mkTerminalFlag = tmuxVar: opt: flag:
     let
-      mkFlag = term: ''set -as terminal-features ",${term}:${flag}"'';
+      mkFlag = term: ''set -as ${tmuxVar} ",${term}:${flag}"'';
       enabledTerminals = lib.filterAttrs (_: v: v.${opt}) cfg.terminalFeatures;
       terminals = lib.attrNames enabledTerminals;
     in
     lib.concatMapStringsSep "\n" mkFlag terminals;
+
+  mkTerminalFeature = mkTerminalFlag "terminal-features";
+  mkTerminalOverride = mkTerminalFlag "terminal-overrides";
 in
 {
   options.my.home.tmux = with lib; {
@@ -28,12 +31,14 @@ in
           hyperlinks = my.mkDisableOption "hyperlinks through OSC8";
 
           trueColor = my.mkDisableOption "24-bit (RGB) color support";
+
+          underscoreStyle = my.mkDisableOption "underscore style/color support";
         };
       });
 
-      default = { ${config.my.home.terminal.program} = { }; };
+      default = { ${config.my.home.terminal.default} = { }; };
       defaultText = literalExpression ''
-        { ''${config.my.home.terminal.program} = { }; };
+        { ''${config.my.home.terminal.default} = { }; };
       '';
       example = { xterm-256color = { }; };
       description = ''
@@ -54,6 +59,20 @@ in
     terminal = "tmux-256color"; # I want accurate termcap info
     aggressiveResize = true; # Automatic resize when switching client size
 
+    # FIXME
+    # * Sixel support
+    # * OSC 133 prompt integration
+    # FIXME: when sensible-on-top is disabled: check if any of those are unset
+    # * tmux bind-key $prefix_without_ctrl last-window
+    # *
+    # * tmux bind-key C-b send-prefix: included
+    # * aggressive resize? done
+    # * tmux bind-key C-p previous-window: done
+    # * tmux bind-key C-n next-window: done
+    # * C-r to refresh my config: done
+    # * tmux set-option -g focus-events on: done
+
+    # FIXME: make PRs for `bind-key` description
     plugins = with pkgs.tmuxPlugins; builtins.filter (attr: attr != { }) [
       # Open high-lighted files in copy mode
       open
@@ -126,6 +145,11 @@ in
       ${mkTerminalFeature "hyperlinks" "hyperlinks"}
       # Force 24-bit color for each relevant $TERM
       ${mkTerminalFeature "trueColor" "RGB"}
+      # Force underscore style/color for each relevant $TERM
+      ${mkTerminalFeature "underscoreStyle" "usstyle"}
+      # FIXME: see https://github.com/folke/tokyonight.nvim#fix-undercurls-in-tmux for additional overrides
+      # ${mkTerminalOverride "underscoreStyle" "Smulx=\\E[4::%p1%dm"}
+      # ${mkTerminalOverride "underscoreStyle" "Setulc=\\E[58::2::::%p1%{65536}%/%d::%p1%{256}%/%{255}%&%d::%p1%{255}%&%d%;m"}
     '';
   };
 }
diff --git a/modules/home/wm/i3/default.nix b/modules/home/wm/i3/default.nix
index 5f22bbe..564aead 100644
--- a/modules/home/wm/i3/default.nix
+++ b/modules/home/wm/i3/default.nix
@@ -3,8 +3,8 @@ let
   isEnabled = config.my.home.wm.windowManager == "i3";
 
   terminal =
-    if config.my.home.terminal.program != null
-    then config.my.home.terminal.program
+    if config.my.home.terminal.default != null
+    then config.my.home.terminal.default
     else "i3-sensible-terminal";
 
   alt = "Mod1"; # `Alt` key
diff --git a/modules/home/wm/rofi/default.nix b/modules/home/wm/rofi/default.nix
index 9707ed7..d0e0215 100644
--- a/modules/home/wm/rofi/default.nix
+++ b/modules/home/wm/rofi/default.nix
@@ -7,7 +7,7 @@ in
     programs.rofi = {
       enable = true;
 
-      terminal = config.my.home.terminal.program; # null by default
+      terminal = config.my.home.terminal.default; # null by default
 
       package = pkgs.rofi.override {
         plugins = with pkgs; [