I am using Nightly, with my own profile and I clear my history every time I close Nightly. And every time I open a new tab with a clean history, I have the "default" new tabs: Facebook, Youtube, Amazon, Yahoo, Twitter... And there is no way to remove/hide any of this. There should be an option to do so. I understand that these would be useful for a first lauch of Firefox / Nightly, but I should be able to choose which ones I want to remove without having to pin other tabs just for removing those I don't care about. Example: I don't care about facebook or ebay, but I am ok to keep twitter and yahoo. It could be done by adding a menu item "Don't show me this anymore" to the ... menu.
There's a preference in the top right corner to turn off top sites. Is that acceptable?
It's a solution, but not really a satisfying one. Because, in that case, I don't see any suggestions anymore: not those I have pinned nor those I have browsed. See, I have pinned 3 sites that I use on a daily basis, they stay even when history is cleared (normal, it's like bookmarks) When I open my browser (clean history), these 3 sites appear on newtab but then "default" new tabs are added and I would like to choose which should not appear because I never visit them, while keeping others I might visit (but not every day). Think of that like the default bookmarks or search engines: nice idea / suggestions but I can remove those I don't want.
Activity Stream should just respect browser.newtabpage.enhanced=false like the old newtab.
It has been fixed for some time now, but I can't remember when exactly. Using 58.0a1 (2017-10-15), I removed some default sites (facebook, ebay) and they don't reappear on the newtab page, even when the history has been cleared.