No New Window on Double Click consists in an extension that prevents Thunderbird from opening a new main window.
This extension prevents Thunderbird from opening a new main window. When you double click on a folder in the folder pane, the folder will expand or collapse if it has subfolders.
Also, when a program tries to run Thunderbird while it is already running, the new window is closed and the first main window will be brought to focus.
New mail windows can still be opened when right-clicking on a folder and selecting Open in New Mail Window.
To install this extension, click on the Download button above and save the file in a convenient location. In Thunderbird, open the Tools menu and select Extensions. Click on the Install button and open the saved extension file.
What's New in This Release:
· Windows opened by right-clicking on a folder and selecting Open in New Mail Window are now allowed.