Britton30 said:
I use Pale Moon for a few sites IE doesn't work well with. It is very slow in startup but blocks almost all those annoying popups.
It's a modified version of FF 24 (which is the "LTS" version).

It's strange that it is slow to start.
In my experience, that is related to having lots of:

  • Lots of Bookmarks
  • Lots of Browsing History data
  • A Corrupted PM (or FF) Profile
  • A Corrupted Add-on

You can start PM in "Safe Mode", just like FF (I just tested it).
Open the Run dialog and type:
palemoon.exe -safe-mode
Tutorial
Firefox - Start Firefox in "Safe Mode"
** Replace firefox.exe with palemoon.exe where necessary.