Recent answers to Adding Rows to Bookmarks Toolbarhttps://support.mozilla.org/en-US/questions/13039162020-09-11T02:50:10-07:00Hi Travis, there's no built-in setting for multi-row toolbars.
The community has developed a workaro2020-09-11T02:50:10-07:00jscher2000https://support.mozilla.org/en-US/questions/1303916#answer-1348708<p>Hi Travis, there's no built-in setting for multi-row toolbars.
</p><p>The community has developed a workaround that involves creating an optional userChrome.css file, a file you can set Firefox to load a startup which allows restyling the toolbar area in various ways.
</p><p>I have a site dedicated to the topic of userChrome.css files: <a href="https://www.userchrome.org/how-create-userchrome-css.html" rel="nofollow">https://www.userchrome.org/how-create-userchrome-css.html</a>
</p><p>This is an example of a style recipe to create a multi-row bookmarks toolbar: <a href="https://github.com/MrOtherGuy/firefox-csshacks/blob/master/chrome/multi-row_bookmarks.css" rel="nofollow">https://github.com/MrOtherGuy/firefox-csshacks/blob/master/chrome/multi-row_bookmarks.css</a>
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