One of my favourite features (after containers) of Firefox is that I can drag the bookmark bar next to the URL bar in customize mode. This is how my Firefox toolbar has looked for many years. It currently has four main category folders (Work, News, Finance, Other), which drop down carefully managed menus with vertical separators (like the one between "Collections" and "Print" in Edge's own main menu) between groups of similar bookmarks, and submenus for subcategories with rarely used links.
In all other browsers (Chrome, Edge, Opera, Vivaldi, etc) bookmarks/favourites feel neglected, like they are actively trying to discourage people from maintaining a bookmark collection by making it primitive and clunky with no grouping except submenus and almost a full line of whitespace between rows. This is Firefox:
This is an area where you have a chance to distinguish yourself from Chrome, Opera and Vivaldi, which are all far behind Firefox when it comes to bookmark management.