1378590 - Addons/Preferences/Customize open a new tab at the end of the tab strip, instead of at current tab

Status: UNCONFIRMED

(Firefox :: Tabbed Browser, defect, P5)

Description

[Asif Youssuff]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:56.0) Gecko/20100101 Firefox/56.0
Build ID: 20170705170343

Steps to reproduce:

1. Open at least two tabs in current browsing session. 

2. Switch to the first tab in the "stack"

3. Open (Any one of) Customize..., Add-Ons, or Preferences. All are available from the new Photon menu, the Customize menu is also available by context clicking on the Firefox toolbar. 


Actual results:

The Customize..., Add-Ons, or Preferences tab is opened as the last tab in the stack -- per the STR, it will be the third tab. 


Expected results:

The Customize..., Add-Ons, or Preferences tab should be the *second* tab per STR. This is my expectation since opening new tabs via ctrl/command click on a link or by context clicking and "open link in new tab" will open new tabs next to my current tab. This expectation does break somewhat if I were to open multiple new tabs from a page; the way this currently works is that new tabs are "stacked" after the last opened tab (and not immediately to the right of the newest created tab) -- which *feels correct* (noting this as a possible caveat here).

The biggest reason aside from the user expectation that this is desirable (perhaps to the tab immediately to the right of the current tab in *all cases*, even when there is a stack of tabs opened from the current tab) is simply because of the janky/non smooth animation of scrolling past a large tab stack to the last tab in a window, along with the immediate fear of loss of context; Firefox does this correctly in that if I close the new tab, it brings me back to my previous tab, but it feels a bit disconcerting every time I do this. 

There have been times where I immediately do a ctrl-shift-tab to get back to my last tab", but this takes me back to the last tab in the window minus one; moving back to the preferences page and closing that tab has lost my context and I have to hunt for my previously used tab again. 

Some more notes; Chrome avoids the janky animation and scroll by compressing each tab into tiny tabs (which I feel is undesirable) and opening a new tab without a scroll. This feels *very* fast even though the core experience is not good (tiny tabs).

Either way, the current Firefox behavior is inconsistent with the way other tabs are opened, and feels slower than it ought to when a user has more tabs than fit without scrolling in a browser window.