1276125 - Firefox doesn't respect about:newtab, so it switches to unwanted tabs consuming RAM and breaks user-defined order of tabs

Status: NEW

(Firefox :: Tabbed Browser, defect)

Description

[arni2033]

>>>   My Info:   Win7_64, Nightly 49, 32bit, ID 20160526082509
Just read STR, no need to actually perform them. They are obvious.

STR_1 (Alt+Enter):
1. Open new window with 41 tabs: 20 tabs with Youtube, 1 selected about:newtab, 20 tabs with Youtube
2. Close and reopen that window
3. Focus urlbar, type "http://www.rp-online.de/", press Alt+Enter

AR:  User-defined order of tabs is broken. about:newtab must be used as separator between tab groups
    (that serves only purpose - don't load simplify navigation without loading unnecessary pending
     tabs). To restore the sane order I have to press Ctrl+T, then drag the opened tab in tab strip
     for a long time searching for correct position.

ER:  Url from Step 3 should open in a new tab



STR_2 (offending pages):
1. Open new window with 41 tabs: 20 tabs with Youtube, 1 selected about:newtab, 20 tabs with Youtube
2. Close and reopen that window
3. Click "Addons" toolbarbutton or "Options" toolbarbutton, or "Home" toolbarbutton.

AR:  To restore the sane order of tabs I have to press Ctrl+T, then drag the opened tab in tab
     strip or a long time searching for correct position, or type "about:newtab" in urlbar.
ER:  Page from Step 3 should open in a new tab

Note: before bug 1014185 Customize page was also offending, but now it isn't (see bug 1252102). I'm
      completely OK with fixing bug 1252102 in a way that will open all offending pages in new tabs
      because about:support, "view source" already open in new tabs.



STR_3 (switch to tab):
1. Open http://example.org/#Unique20160527123456 in a new tab
2. Open new window with 41 tabs: 20 tabs with Youtube, 1 selected about:newtab, 20 tabs with Youtube
3. Close and reopen that window
4. Paste "Unique20160527123456" in urlbar, then click autocomplete suggesetion "switch to tab"

AR:  Tabs order is broken. Browser consumes a lot of extra RAM and produces loud sound from Youtube
ER:  Tabs order shouldn't be broken; I didn't ask the browser to load that page, so it shouldn't.



STR_4 (switch to tab 2):
1. Open http://example.org/#Unique20160527123456 in a new tab
2. Open new window, open new tab, close all other tabs.
3. Open 5 tabs with http://ya.ru/ , then close them [you'll end up with only about:newtab].
4. Type "a" in searchbar, type "b" in findbar.
5. Open devtools -> performance, load a profile to explore it in a light tab.
   Open devtools -> memory, do the same.
6. Paste "Unique20160527123456" in urlbar, then click autocomplete suggesetion "switch to tab"

AR:  The whole window with my closed tabs, typed input and progress in devtools is closed
ER:  There should be an easy way to re-obtain all progress achieved in Steps 1-5


Generalization:
AR:  Browser acts completely illogical and malicious when it comes to about:newtab
ER:  There should be an easy way to obtain not broken behavior - a fix, a pref, or an official
     extension that would provide a non-blinking page with an empty, initially focused urlbar.
     A page that wouldn't have all said bugs.


_Every_ time an ingenious idea on "improving" UX is implemented, UX of a real user is significantly broken. I listed a few examples in bug 1251071 comment 7. Please read it and don't "improve" anymore.