1433027 - Top thick border of current tab is out of tune with themes!!

Status: UNCONFIRMED

(Firefox :: Theme, defect, P5)

Description

[Yankit Leung]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0
Build ID: 20180122144853

Steps to reproduce:

Enable any lightweight themes on Firefox 58 or newer


Actual results:

When using themes, the active tab indicator (top border) on tab bar is usually black in color, which is very dissonant with the background images of most of the themes. Especially when window is maximized, it looks like a broken edge on the display.


Expected results:

The top thickened border of the active tab should be in the same color as borders around the tab, which is originally with opacity that can just reconcile with any themes.

Example: userChrome.css
:root:-moz-lwtheme {--tab-line-color: var(--tabs-border-color) !important;}

Even after this change, the active tab is still very obvious. In addition to the thick top border, both address bar and active tab having same background transparency adequately makes it distinct from other tabs.