Right click and remove As to where removed to would hope to Customize. But not sure.

Please let us know if this solved your issue or if need further assistance.

I was able to remove the Star icon, but the "•••" icon and reader icon are still there. When I right mouse on both, the choice to "Remove from Toolbar" is grayed out. We're getting there, but we ain't there yet!

You can remove the 3 dots (known as the Page Action menu) by adding the below to a userChrome.css file

#page-action-buttons { display: none !important; }

• https://www.userchrome.org/what-is-userchrome-css.html