This is an extremely simple and lightweight extension that adds support for using the back/forward buttons on the mouse for navigating back/forward in code. Pressing these buttons simply executes the Navigate Backward (default Ctrl+-) or Navigate Forward (default Ctrl+Shift+-) as appropriate.
If you encounter any cases where this extension does not behave the same way as pressing the navigation buttons in the toolbar, please let me know.
💡 Note for Logitech users: The Logitech software has been known to conflict with this extension. If you find the extension not working, see tunnelvisionlabs/MouseNavigation#5 (comment) for a potential solution.