Hi   !
You can set the startup (home) page to   about:newtab

Tools => Options => General => Startup : Home page

https://support.mozilla.org/kb/How+to+set+the+home+page

Note that Firefox supports multiple home pages separated by   '|'   (pipe) symbols.

You can use pages like these:

the default new tab page with the tiles is   about:newtab the default home page is   about:home for a blank page use   about:blank

That is not possible. You can't open only pinned tabs. Firefox will always open at least one normal tab on startup. You can modify the desktop shortcut and add about:blank or another built-in page (see about:about) to the target line to start with that specific page instead of the home page or set the startup page to a blank page.

Well that stinks. Chrome, here I come.