diff --git a/ext/src/_locales/es/messages.json b/ext/src/_locales/es/messages.json
new file mode 100644
index 0000000..89dcab7
--- /dev/null
+++ b/ext/src/_locales/es/messages.json
@@ -0,0 +1,298 @@
+{
+    "extensionName": {
+        "message": "EXTENSION_NAME"
+      , "description": "Name of the extension and the native receiver selector window title."
+    }
+  , "extensionDescription": {
+        "message": "Habilita el soporte de Chromecast para transmitir aplicaciones web (como Netflix y BBC iPlayer), video HTML5 y enviar pantalla/pestañas."
+      , "description": "Description of the extension shown in the add-ons manager."
+    }
+
+
+  , "popupMediaTypeApp": {
+        "message": "la aplicación de este sitio"
+      , "description": "Receiver selector media type <option> text for current site's sender application."
+    }
+  , "popupMediaTypeTab": {
+        "message": "Pestaña"
+      , "description": "Receiver selector media type <option> text for current tab."
+    }
+  , "popupMediaTypeScreen": {
+        "message": "Pantalla"
+      , "description": "Receiver selector media type <option> text for screen."
+    }
+  , "popupMediaTypeFile": {
+        "message": "Examinar..."
+      , "description": "Receiver selector media type <option> text for opening a file selector dialog."
+    }
+
+  , "popupMediaSelectCastLabel": {
+        "message": "Transmitir"
+      , "description": "(Cast) <select> to:"
+    }
+  , "popupMediaSelectToLabel": {
+        "message": "a:"
+      , "description": "Cast <select> (to:)"
+    }
+  , "popupCastButtonTitle": {
+        "message": "Transmitir"
+      , "description": "Button text for each receiver entry in the receiver selector."
+    }
+  , "popupCastingButtonTitle": {
+        "message": "Transmitiendo$ellipsis$"
+      , "description": "Button text while establishing a session in the receiver selector. Ellipsis cycles (. → .. → ...) as loading indicator."
+      , "placeholders": {
+            "ellipsis": {
+                "content": "$1"
+              , "example": "..."
+            }
+        }
+    }
+
+
+  , "contextCast": {
+        "message": "Transmitir a..."
+      , "description": "Main context menu item title. Ellipsis indicates additional information required as it triggers opening of receiver selector."
+    }
+
+  , "contextAddToWhitelist": {
+        "message": "Añadir a la lista blanca"
+      , "description": "Top-level whitelist context menu item title."
+    }
+  , "contextAddToWhitelistRecommended": {
+        "message": "Añadir $matchPattern$ (Recomendado)"
+      , "description": "Context menu item title for recomended match pattern."
+      , "placeholders": {
+            "matchPattern": {
+                "content": "$1"
+              , "example": "https://example.com/*"
+            }
+        }
+    }
+  , "contextAddToWhitelistAdvancedAdd": {
+        "message": "Añadir $matchPattern$"
+      , "description": "Context menu item title for all other match patterns."
+      , "placeholders": {
+            "matchPattern": {
+                "content": "$1"
+              , "example": "*://*.example.com/*"
+            }
+        }
+    }
+
+
+  , "optionsBridgeLoading": {
+        "message": "Cargando información de la aplicación puente..."
+      , "description": "Loading placeholder text for bridge section on options page."
+    }
+  , "optionsBridgeFoundStatusTitle": {
+        "message": "Aplicación puente encontrada"
+      , "description": "Bridge OK status title text."
+    }
+  , "optionsBridgeIssueStatusTitle": {
+        "message": "Problema con aplicación puente"
+      , "description": "Bridge error status title text."
+    }
+  , "optionsBridgeNotFoundStatusTitle": {
+        "message": "Aplicación puente no encontrada"
+      , "description": "Bridge missing status title text."
+    }
+  , "optionsBridgeNotFoundStatusText": {
+        "message": "Intente descargar e instalar la última versión."
+      , "description": "Bridge not found additional description text"
+    }
+
+  , "optionsBridgeStatsName": {
+        "message": "Nombre:"
+      , "description": "Bridge stats name row title."
+    }
+  , "optionsBridgeStatsVersion": {
+        "message": "Versión:"
+      , "description": "Bridge stats version row title."
+    }
+  , "optionsBridgeStatsExpectedVersion": {
+        "message": "Versión esperada:"
+      , "description": "Bridge stats expected version row title."
+    }
+  , "optionsBridgeStatsCompatibility": {
+        "message": "Compatibilidad:"
+      , "description": "Bridge stats compatibility row title."
+    }
+  , "optionsBridgeStatsRecommendedAction": {
+        "message": "Acción recomendada:"
+      , "description": "Bridge stats recommended action row title."
+    }
+  , "optionsBridgeCompatible": {
+        "message": "COMPATIBLE"
+      , "description": "Compatibility status is definitely compatible."
+    }
+  , "optionsBridgeLikelyCompatible": {
+        "message": "PROBABLEMENTE COMPATIBLE"
+      , "description": "Compatibility status is probably compatible."
+    }
+  , "optionsBridgeIncompatible": {
+        "message": "INCOMPATIBLE"
+      , "description": "Compatibility status is definitely incompatible."
+    }
+  , "optionsBridgeOlderAction": {
+        "message": "Versión de la aplicación puente inferior a la esperada, intente actualizarla a la última versión."
+      , "description": "Recommended action for when the installed bridge version is older than the installed extension version."
+    }
+  , "optionsBridgeNewerAction": {
+        "message": "Versión de la aplicación puente superior a la esperada, intente actualizar la extensión a la última versión."
+      , "description": "Recommended action for when the installed bridge version is newer than the installed extension version."
+    }
+  , "optionsBridgeNoAction": {
+        "message": "No se requieren acciones."
+      , "description": "Recommended action for when both bridge and extension versions are compatible or likely compatible."
+    }
+  , "optionsBridgeUpdateCheck": {
+        "message": "Buscar actualizaciones"
+      , "description": "Update check button title."
+    }
+  , "optionsBridgeUpdateChecking": {
+        "message": "Buscando actualizaciones para Updates$ellipsis$"
+      , "description": "Update check button title while in progress. Ellipsis cycles (. → .. → ...) as loading indicator."
+      , "placeholders": {
+            "ellipsis": {
+                "content": "$1"
+              , "example": ".."
+            }
+        }
+    }
+  , "optionsBridgeUpdateStatusNoUpdates": {
+        "message": "No hay actualizaciones disponibles"
+      , "description": "Update status if no updates are found."
+   }
+  , "optionsBridgeUpdateStatusError": {
+        "message": "Error al buscar actualizaciones"
+      , "description": "Update status if an error was encountered checking for updates."
+   }
+  , "optionsBridgeUpdateAvailable": {
+        "message": "Hay una actualización disponible:"
+      , "description": "Update status if an update was found."
+   }
+  , "optionsBridgeUpdate": {
+        "message": "Actualizar ahora..."
+      , "description": "Update now button title. Ellipsis indicates additional information as it triggers an update window popup."
+    }
+
+  , "optionsMediaCategoryName": {
+        "message": "Transmisión de contenidos"
+      , "description": "Options page media casting category title."
+    }
+  , "optionsMediaCategoryDescription": {
+        "message": "Transmisión de video/audio HTML5."
+      , "description": "Options page media casting category description."
+    }
+  , "optionsMediaEnabled": {
+        "message": "Activar transmisión de contenidos"
+      , "description": "Media casting enabled checkbox label."
+    }
+  , "optionsMediaSyncElement": {
+        "message": "Sincronizar estado del receptor con el contenido"
+      , "description": "Media casting sync checkbox label."
+    }
+  , "optionsMediaStopOnUnload": {
+        "message": "Detener reproducción del receptor al cerrar la página"
+      , "description": "Media stop on unload checkbox label."
+    }
+
+  , "optionsLocalMediaCategoryName": {
+        "message": "Transmisión de contenidos locales"
+      , "description": "Options page local media category title."
+    }
+  , "optionsLocalMediaCategoryDescription": {
+        "message": "Servidor HTTP iniciado por la aplicación puente para transmitir archivos de medios locales al receptor."
+      , "description": "Options page local media category description."
+    }
+  , "optionsLocalMediaEnabled": {
+        "message": "Activar transmisión de medios locales"
+      , "description": "Local media enabled checkbox label."
+    }
+  , "optionsLocalMediaServerPort": {
+        "message": "Puerto del servidor HTTP:"
+      , "description": "HTTP server port input label."
+    }
+
+  , "optionsUserAgentWhitelistCategoryName": {
+        "message": "Lista blanca de agentes de usuario"
+      , "description": "Options page whitelist category title."
+    }
+  , "optionsUserAgentWhitelistCategoryDescription": {
+        "message": "Sitios en los cuales reemplazar el agente de usuario con una versión de Chrome para compatibilidad. Deben ser patrones de coincidencia válidos."
+      , "description": "Options page whitelist category description."
+    }
+  , "optionsUserAgentWhitelistEnabled": {
+        "message": "Activar lista blanca de sitios"
+      , "description": "Whitelist enabled checkbox label."
+    }
+  , "optionsUserAgentWhitelistContent": {
+        "message": "Patrones de coincidencia (uno por línea):"
+      , "description": "Match patterns editor widget label."
+    }
+  , "optionsUserAgentWhitelistBasicView": {
+        "message": "Vista básica"
+      , "description": "Switch to basic view button title."
+    }
+  , "optionsUserAgentWhitelistRawView": {
+        "message": "Vista en bruto"
+      , "description": "Switch to raw view button title."
+    }
+  , "optionsUserAgentWhitelistSaveRaw": {
+        "message": "Guardar archivo en bruto"
+      , "description": "Save raw view edits button title."
+    }
+  , "optionsUserAgentWhitelistAddItem": {
+        "message": "Añadir elemento"
+      , "description": "Add new whitelist item button title."
+    }
+  , "optionsUserAgentWhitelistEditItem": {
+        "message": "Editar"
+      , "description": "Edit whitelist item button title. Displayed on each item."
+    }
+  , "optionsUserAgentWhitelistRemoveItem": {
+        "message": "Eliminar"
+      , "description": "Remove whitelist item button title. Displayed on each item."
+    }
+  , "optionsUserAgentWhitelistInvalidMatchPattern": {
+        "message": "Patrón de coincidencia $matchPattern$ inválido"
+      , "description": "Error displayed by input indicating an invalid match pattern."
+      , "placeholders": {
+            "matchPattern": {
+                "content": "$1"
+              , "example": "http://example"
+            }
+        }
+    }
+
+  , "optionsMirroringCategoryName": {
+        "message": "Enviar pantalla"
+      , "description": "Options page mirroring category name."
+    }
+  , "optionsMirroringCategoryDescription": {
+        "message": "Envío de pantalla/pestaña a la aplicación receptora de Chromecast."
+      , "description": "Options page mirroring category description."
+    }
+  , "optionsMirroringEnabled": {
+        "message": "Activar envío de pantalla"
+      , "description": "Mirroring enabled checkbox label."
+    }
+  , "optionsMirroringAppId": {
+        "message": "ID de aplicación receptora:"
+      , "description": "Mirroring app ID input label."
+    }
+
+  , "optionsReset": {
+        "message": "Restaurar predeterminados"
+      , "description": "Restore default options button label."
+    }
+  , "optionsSave": {
+        "message": "Guardar"
+      , "description": "Save options button label."
+    }
+  , "optionsSaved": {
+        "message": "¡Guardado!"
+      , "description": "Status text displayed by save button once options have been successfully saved."
+    }
+}