Accessing my PC's bookmarks is one of the main reasons I transitioned from Safari. but currently accessing your bookmarks is rather tedious. The Firefox iOS app should allow you to put your bookmarks on your homepage.
I've curated hundreds of bookmarks over the years time, and I actually want to use them. It's a bit disappointing to see "Shortcuts" on the main page. All the auto-generated ones are useless. Why should I need to create a whole host of new Shortcuts when I've already got them bookmarked?