diff --git a/src/app/browser.hpp b/src/app/browser.hpp
index f2debd9..a94dd4b 100644
--- a/src/app/browser.hpp
+++ b/src/app/browser.hpp
@@ -71,9 +71,9 @@ namespace app
             app::browser::Main * browserMain;
 
             // Defaults
-            const int WIDTH = 640;
-            const int HEIGHT = 480;
-            const bool IS_FULLSCREEN = false;
+            static const int WIDTH = 640;
+            static const int HEIGHT = 480;
+            static const bool IS_FULLSCREEN = false;
 
         /*
          * Browser class API
diff --git a/src/app/browser/header.hpp b/src/app/browser/header.hpp
index be7c834..9cc105d 100644
--- a/src/app/browser/header.hpp
+++ b/src/app/browser/header.hpp
@@ -24,7 +24,7 @@ namespace app::browser
         header::Tab * headerTab;
 
         // Defaults
-        const bool SHOW_TITLE_BUTTONS = true;
+        static const bool SHOW_TITLE_BUTTONS = true;
 
         public:
 
diff --git a/src/app/browser/main.hpp b/src/app/browser/main.hpp
index c3703ca..74b8ea2 100644
--- a/src/app/browser/main.hpp
+++ b/src/app/browser/main.hpp
@@ -66,7 +66,7 @@ namespace app::browser
             main::Tab * mainTab;
 
             // Defaults
-            const bool HOMOGENEOUS = true;
+            static const bool HOMOGENEOUS = true;
 
         /*
          * Main class API
diff --git a/src/app/browser/main/tab.hpp b/src/app/browser/main/tab.hpp
index bd0c01e..716841a 100644
--- a/src/app/browser/main/tab.hpp
+++ b/src/app/browser/main/tab.hpp
@@ -75,8 +75,8 @@ namespace app::browser::main
                                             action__update;
 
             // Defaults
-            const bool REORDERABLE = true;
-            const bool SCROLLABLE = true;
+            static const bool REORDERABLE = true;
+            static const bool SCROLLABLE = true;
 
         /*
          * Tab class API
diff --git a/src/app/browser/main/tab/label.hpp b/src/app/browser/main/tab/label.hpp
index b928e56..b8ce617 100644
--- a/src/app/browser/main/tab/label.hpp
+++ b/src/app/browser/main/tab/label.hpp
@@ -64,7 +64,7 @@ namespace app::browser::main::tab
             Glib::RefPtr<Gio::SimpleAction> action__tab_close;
 
             // Defaults
-            int WIDTH_CHARS = 16;
+            static const int WIDTH_CHARS = 16;
 
         /*
          * Class API
diff --git a/src/app/browser/main/tab/page/content/text/gemini/reader.hpp b/src/app/browser/main/tab/page/content/text/gemini/reader.hpp
index 9f0fb47..4cb5e4f 100644
--- a/src/app/browser/main/tab/page/content/text/gemini/reader.hpp
+++ b/src/app/browser/main/tab/page/content/text/gemini/reader.hpp
@@ -72,8 +72,8 @@ namespace app::browser::main::tab::page::content::text::gemini
         Glib::RefPtr<Gio::SimpleAction> action__open_link_variant;
 
         // Defaults
-        const int MARGIN_START = 8;
-        const int MARGIN_END = 8;
+        static const int MARGIN_START = 8;
+        static const int MARGIN_END = 8;
 
         /*
          * Reader class API
diff --git a/src/app/browser/main/tab/page/navigation.hpp b/src/app/browser/main/tab/page/navigation.hpp
index 8a871b1..66eef30 100644
--- a/src/app/browser/main/tab/page/navigation.hpp
+++ b/src/app/browser/main/tab/page/navigation.hpp
@@ -72,8 +72,8 @@ namespace app::browser::main::tab::page
             navigation::Request * navigationRequest;
 
             // Defaults
-            const int SPACING = 8;
-            const int MARGIN = 8;
+            static const int SPACING = 8;
+            static const int MARGIN = 8;
 
         /*
          * Class API
diff --git a/src/app/browser/main/tab/page/navigation/request.hpp b/src/app/browser/main/tab/page/navigation/request.hpp
index 8ab78c6..46c5a11 100644
--- a/src/app/browser/main/tab/page/navigation/request.hpp
+++ b/src/app/browser/main/tab/page/navigation/request.hpp
@@ -69,9 +69,9 @@ namespace app::browser::main::tab::page::navigation
             sigc::connection progress_connection;
 
             // Defaults
-            const bool HEXPAND = true;
-            const double PROGRESS_PULSE_STEP = .1;
-            const int PROGRESS_ANIMATION_TIME = 10;
+            static const bool HEXPAND = true;
+            static const int PROGRESS_ANIMATION_TIME = 10;
+            const double PROGRESS_PULSE_STEP = .1; // @TODO static?
 
         /*
          * Class API