If you care about browser extension support, Firefox is a tough sell. It doesn't run the millions of Chrome extensions out there, so you'll have far fewer add-on options unless developers specifically rebuild them for Firefox. That means you're much more likely to run into missing features or have to use a second browser for anything that needs full Chrome extension compatibility.
Toby, on the other hand, is itself a browser extension. It's designed to give you a prettier new tab page and some lightweight tab management, but it doesn't go deep into solving real tab chaos. It's only for people who want something very basic and visual, not for heavy tab management workflows.
If what you're really after is broad browser extension support or the ability to run serious tab management tools, Firefox just won't cut it for most people because of its limited ecosystem. Toby is only an option if you're on a Chromium-based browser, since that's where most extensions and deeper features live anyway.
So if extensions matter at all, skip Firefox. Toby only scratches the surface for tab management, but at least it runs in the environment where you'll actually have access to the full extension ecosystem.