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

Thunderbird, Postbox

Status Bar

Toggle The Status Bar

Toggle the status bar from hidden to shown. Hide it to get the most out of your screen space, and show it when it really needed.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Toggle Toolbar

Toggle the Main Toolbar

Toggle the main toolbar from showing to hidden. Don't place it on the main toolbar, it is disabled then and will not work.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Update

Check For Updates

Check for updates to the currently open application.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

about:plugins

Open about:plugins to view installed plugins

Open about:plugins to view installed plug-ins.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Codefisher

Open Codefisher.org

Opens various pages of the Codefisher.org website.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Cookie Exceptions

Open the Cookie Exceptions dialog

Open the cookie exceptions dialog.

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

Error Console

Open the Error Console

Open the error console to view errors caused by scripts.

The error console is every developers best friend. Trying to find the line where you went wrong can be very hard with out so clue particularly in long or complex scripts. It shows errors from JavaScript, CSS, XML and even from the program itself should that be enabled.

If the error console is disabled, this button will, depending on its setting, open the "Web Console" or "Browser Console" which now serve the same function.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Get Extensions

Get more Thunderbird extensions

Open addons.mozilla.org on the page to get more Thunderbird extensions. Link can be change using about:config if you prefer another site.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey

Hide Toolbars

Toggle visibility of all toolbars, except the main toolbar

Toggle the visibility of all toolbar, other then the main toolbar.

Compatibility: Pale Moon Thunderbird, Postbox SeaMonkey