It literally does what it says. Drag it to wherever you need. Flexible, useful, amazing!
Found it works well just being pinned and the extension icon works great too!

Works perfectly and is exactly as advertised. Unfortunate that there can only be one divider but it's better than nothing.

A singular divider. Worthless.

...un'estensione per poter aggiungere un separatore! Assurdo Firefox! Grazie all'autore per l'estensione, se si riuscisse ad aggiungerne più di una sarebbe ancora meglio!

Thank you for this. As the author explained below, this add-on can provide only one divider.

If you'd like several separators-like, you may want to right click at the toolbar > add "Flexible Space" (as many times as you need). By default "Flexible Space" takes too much space. However, you can customize it as per https://www.reddit.com/r/FirefoxCSS/comments/8kt4k1/nav_bar_small_flexible_spaces_or_separators.

Mozilla needs to re-add separators to Firefox.

Hi,

can you please add an option to enable more dividers?

Thanks,
Hyper

It would be very appreciated if the author would look into how others have worked around the single context menu option or single toolbar button per extension issue. There are ways, such as downloading copies of the extension file with slight name/GUID modifications, ie: divider, divider1, divider2, etc.

Simple, yet useful. I know there is a limit of 1 button per extension, but maybe you could just add multiple copies of your extension? Like divider_1, divider_2, divider_3, etc.

As already mentioned below, only one limited separator is the problem.

Works as advertised, both in the main toolbar or in the Overflow menu.

However, only supporting one divider is an unfortunate limitation which makes it less flexible or generally useful.