Hello?????

Hi James.

What do you mean that you cannot find it even though you keep installing it? Does the add-on appear on the page of installed add-ons (access under the tools menu)?

I mean I used to be able to install the add-on. Now I can't seem to find it.

What is the name of the add-on?

I believe it was called 'Customize header toolbar.'

Here's a screen shot of the toolbar.

It is called "Message Header Toolbar Customize". It is still available and it works with Thunderbird 140.0.

Tools (menu) > Add-ons & Themes" or the three-line icon > Add-ons & Themes. Then search for "Message Header Toolbar Customize".

There is a way to remove that toolbar using CSS, which is quite simple. https://superuser.com/questions/1802457/thunderbird-remove-icons-reply-forward-archive-from-message-header-toolb

The add-on is called Message Header Toolbar Customize. Note, there is no such thing as a 'message body toolbar'. You need the version 2.4.4 with the date Apr 07, 2025 if you are using a version of TB more recent than 136. You can download it here. https://hogi.sakura.ne.jp/en/downloadcgi.rhtml?msghdrcust

Got it, thanks. I must have tried 10 combinations similar to the title and had no luck,

Thanks again.

When your problem is fixed, can you mark the topic as 'Solved' please?