How to get MultiRow bookmarks back in Firefox 57+ and fix for Firefox 66+

Edit: Now includes a fix for Firefox 66+.

I’m a big fan of using multirow bookmarks in browsers. First I used the multirow bookmarks plus addon for Firefox, and when that no longer worked I used Roomy Bookmarks addon to my full satisfaction. I even held back updating Firefox to 57 for a while, as the research part of my working life is organized around bookmarks, so I was in despair.

Luckily, there is a fix. So go ahead and upgrade to Firefox 57 if this issue was holding you back.

Steps to get multirow bookmarks back in Firefox 57 and newer:

Step 1: Create a file called userChrome.css in a folder called chrome in your Firefox profile.

This picture explains how to get there:

Step 2: Paste this code in the file userChrome.css and save the file:

/* Multi-Row Bookmarks Toolbar */
#PersonalToolbar {
/* Provide room for up to 4 rows at 26px */
max-height: 104px !important;
}
#PlacesToolbarItems > box {
display: inline-block !important;
}
#PersonalToolbar #PlacesToolbarItems {
/* Override hiding */
overflow-x: visible !important;
overflow-y: visible !important;
/* Add a little cushion */
padding-bottom: 1px;
}
#PersonalToolbar #PlacesToolbarItems .bookmark-item {
/* Reduce padding on individual bookmarks to fit rows closer together */
padding-top: 1px !important;
padding-bottom: 1px !important;
}

Step 3 (optional): If you prefer to autohide the bookmarks toolbar, additionally add this code in the file userChrome.css and save the file:

/* Auto-hide bookmarks toolbar */
PersonalToolbar {

visibility: collapse !important;
position: fixed;
width: 100%;
border-bottom: 1px solid #A8A8A8 !important;

}
navigator-toolbox:hover > #PersonalToolbar {

visibility: visible !important;

}

Step 4: Restart Firefox

And voila, there is your trusted multirow bookmarks!