Links not opening in the browser or two windows opening on click

If links are not opening up in the browser, or if two tabs/windows are opening on each click, here are few things to try:

Reset your default browser

Change your default browser to another browser and then change it back. In some scenarios after a browser update, the OS setting for the default browser fails to get updated.

Does it work on other browsers except Chrome? Chrome may be in process of updating. Make sure Chrome up to date and restart it.


Make sure Postbox is set to use your system default

  1. Open the Preferences window.
    • (Mac) On the menu bar, open the Postbox menu, and go to Preferences.
    • (Windows) On the menu bar, open the Tools menu, and go to Options.
  2. Select the Advanced panel, and make sure the General tab is selected.
  3. Click on Config Editor.
  4. Click on I'll be careful, I promise.
  5. In the Filter field, paste the following preference: network.protocol-handler.external-default
  6. Right-click on the row for that preference, and select Reset.
  7. Repeat the previous two steps for the following preferences:
    • network.protocol-handler.warn-external.http
    • network.protocol-handler.warn-external.https

Certain add ons (like ThunderBrowse) can leave these hidden prefs in the wrong state after uninstall.

Install ThunderBrowse

If the above steps don't help, it's recommended to reinstall ThunderBrowse, change a preference, and then uninstall it again. Here's how:
  1. Go to the ThunderBrowse website and download the latest version: 
  2. Open Postbox, and go to Tools > Add-ons, and click the action button at the top right corner to install it. 
  3. Once it's installed, restart Postbox.
  4. Go back to Tools > Add-ons and click the Preferences button next to ThunderBrowse 
  5. In the resulting window, click the Links tab, and check the option to Disable ThunderBrowse link loading.
  6. Click a link and verify that it now loads in your default browser. 
  7. Disable/Uninstall ThunderBrowse, and restart Postbox to make sure links still open in your default browser