Hello! I don't know what you mean by "verification icon", but you can edit the browser toolbar by: Customize Firefox controls, buttons and toolbars

I believe barton.ra is referring to the shield or the padlock in the address bar. The only way I know to hide either is by using userChrome.css. I don't know the css selectors for those items but they can be ascertained, probably, by using the Browser Content Toolbox. Note the blank space has to be removed in the link below.

https://www.userchrome. org/how-create-userchrome-css.html