• Install uBlock Origin and block unwanted ads.
  • Install a password manager extension. I recommend 1Password
  • Add keyword search for websites that you search often. This makes it possible for you to perform website searches through the browser address bar. For example, I set a as the keyword search for Amazon. I can then type a science fiction books in the address bar, and it'll then take me to Amazon's search results. https://support.mozilla.org/en-US/kb/how-search-from-address-bar
  • Don't overdo the tabs. I used to use a tree style sidebar extension, but I found that it encouraged me to keep a large number of tabs opened for an indefinite period.  So I ditched that. If a tab needs to be opened for a long time to be referenced, I just save it as a bookmark.