Add keyboard shortcut

Added Ctrl+T to open DeepL.

Thunderbird/background.js

@@ -33,3 +33,15 @@ messenger.menus.onClicked.addListener((info, tab) => {
     break;
   }
 });
+
+messenger.commands.onCommand.addListener((command) => {
+  switch (command) {
+  case "deepl":
+    messenger.Helper.getSelectedText().then(text => {
+      if (text && text.match(/\S/g)) {
+        goDeepL(text);
+      }
+    });
+    break;
+  }
+});

Thunderbird/helper.js

@@ -0,0 +1,13 @@
+var { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+
+var Helper = class extends ExtensionCommon.ExtensionAPI {
+  getAPI(context) {
+    return {
+      Helper: {
+        async getSelectedText() {
+          return Services.wm.getMostRecentWindow("mail:3pane").document.commandDispatcher.focusedWindow.getSelection().toString();
+        }
+      }
+    };
+  }
+};

Thunderbird/helper.json

@@ -0,0 +1,14 @@
+[
+  {
+    "namespace": "Helper",
+    "functions": [
+      {
+        "name": "getSelectedText",
+        "type": "function",
+        "description": "Get selected text.",
+        "async": true,
+        "parameters": []
+      }
+    ]
+  }
+]

Thunderbird/manifest.json

@@ -19,11 +19,27 @@
     "menus",
     "storage"
   ],
+  "commands": {
+    "deepl": {
+      "suggested_key": { "default": "Ctrl+T" },
+      "description": "Translate selected text with DeepL"
+    }
+  },
   "background": {
     "scripts": [
       "background.js"
     ]
   },
+  "experiment_apis": {
+    "Helper": {
+      "schema": "helper.json",
+      "parent": {
+        "scopes": ["addon_parent"],
+        "paths": [["Helper"]],
+        "script": "helper.js"
+      }
+    }
+  },
   "options_ui": {
     "page": "options.html",
     "browser_style": true,