These are a ready make selection of some of the most popular buttons from the Custom Toolbar Button Maker

Thunderbird, Postbox

Toggle menu bar

Toggle the menu bar

Toggle the menu bar. Don't put this button on the menu bar!

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Work Offline

Toggle work offline

Toggle Work Offline and Work Online.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Extensions

Open Extension Manager

Open the Extensions Manager to install, uninstall or do any other needed tasks to any of your extensions.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Open

Open a File

Open a file stored on your local hard drive. Can be used to install extensions or themes.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Print Preview

Open Print Preview

Open the Print Preview to view a page before printing it.

Paper costs money (and trees) so it is worth checking what the page looks like before you print it. Though it has always amazed me just how much the button gets downloaded.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Reset Zoom

Reset Text Size

Reset Text Size to the default setting.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Toolbars

Hide/Show Toolbars

Show and hide toolbars quickly and easily.

Toolbars use up valuable screen real estate, removing them frees this up to show more web page or email depending on what your doing.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Customize Toolbar

Customize toolbar, add or remove buttons etc.

Open the customize toolbar window to add or remove items from your toolbar.

The customize Toolbar window is where every button from this extension and others like it get placed for you to then move to your toolbar. Creating the perfect set up is always a moving target that is never quite achieved, but this will make it a little quicker to get there.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Exit

Exit Application

This button not only closes the current window, but every one that the current application may have open. It is a lot quicker than finding all windows and closing them one at a time.

Finished browsing or reading all your emails, left lots of windows open? Don't want to have to shut them all one at a time? This little button can close them all, with out you having to do it all.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

File Menu

Show the file menu

Show the file menu.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey