1 files changed, 39 insertions, 0 deletions
diff --git a/comm/mail/modules/MailConsts.jsm b/comm/mail/modules/MailConsts.jsm
new file mode 100644
index 0000000000..38c219702a
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+++ b/comm/mail/modules/MailConsts.jsm
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This is a place to store constants and enumerations that are needed only by
+ * JavaScript code, especially component/module code.
+ */
+
+var EXPORTED_SYMBOLS = ["MailConsts"];
+
+var MailConsts = {
+  /**
+   * Determine how to open a message when it is double-clicked or selected and
+   * Enter pressed. The preference to set this is mail.openMessageBehavior.
+   */
+  OpenMessageBehavior: {
+    /**
+     * Open the message in a new window. If multiple messages are selected, all
+     * of them are opened in separate windows.
+     */
+    NEW_WINDOW: 0,
+
+    /**
+     * Open the message in an existing window. If multiple messages are
+     * selected, the fallback is to "new window" behavior. If no standalone
+     * windows are open, the message is opened in a new standalone window.
+     */
+    EXISTING_WINDOW: 1,
+
+    /**
+     * Open the message in a new tab. If multiple messages are selected, all of
+     * them are opened as tabs, with the last tab in the foreground and all the
+     * rest in the background. If no 3-pane window is open, the message is
+     * opened in a new standalone window.
+     */
+    NEW_TAB: 2,
+  },
+};