Sleipnir 4.5.2
I use this browser now and then, but I feel it requires the option of adding a pop-up blocker. I had a pop-up come up within the hour and saying that I had Malware and to call the phone number posted. It also prevending me from the tab that it came up on. I eventually got rid of it by using the "Froce Quit Applications" that is part of Apple Software. I am using system 10.11.5 in case you are interested. That is all I can say for now, otherwise Sleipnir is pretty lean and operates rather quickly. However, again, the concern here is the pop-up situation which could be a little tricky and maybe dangerous to your well being.
Mark Holt about Sleipnir, v4.5.2