Hi, do not the Bookmarks Toolbar go into the over flow menu (2 arrows right side same line as the bookmarks) when you run out of room in the Bookmarks Toolbar ?

Are you running any extensions for the New Tab Page that is allowing the 2 rows ? Please supply name of extension if you are and please provide screen shots: https://support.mozilla.org/en-US/kb/firefox-screenshots

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

Tom,

This not the place to request new or changed features in Firefox. This if the "input" / Feedback page - https://qsurvey.mozilla.com/s3/FirefoxInput/ - which is the proper place to contact Firefox with such requests.

I'm not too sure how much you know of this but in the meantime -

One at a time, right click on each item on the Bookmarks Toolbar. Click on Properties(at the end) and you can abbreviate the name right down to just the Icon if you wish. Remember, to save space that you can also create Folders on your Toolbar to group similar bookmarks(right click on the toolbar; also offers new separators). Also don't be afraid of the easily accessed spillover - >> at the end of the Bookmarks Toolbar.

[Addition] Many of us value the page space more than an extra toolbar but Firefox should realise that many would value the option of an extra toolbar. I'm not sure if the old extension with the name like "Multi-rows toolbar" can be resurrected.