mlamouri@, can you please specify which OS, Chrome version, and Chrome channel you're using? This can be found at chrome://version.

I'm on Linux running Chrome 51 (Beta).
Exact version is 51.0.2704.22.

(removing owner who was set by mistake)

Thanks for clarifying.

Evan, are the colors in the attached screenshot WAI for Linux?

this is also true of cros, although in addition to the frame color difference the focused window has a heavy shadow on it. +sgabriel to decide if we should worry about this since we can't depend on how the WM indicates focus on Linux.

+aboxhall@ for a11y POV.

My guess it that since the frame is the only thing changing (vs frame+shadow+controls on cros or entire core UI theming on OSX), we'd need to go for a really strong color difference to actually notice a difference. Even for the extreme case like OSX where we modify the entire theme, people still get the windows confused.

I don't think making it lighter would benefit recognition greatly, it will hurt the visual design however. 

I do not think accessibility should be taken into account here as this is non critical and not affecting the usage of Chrome. My assumption is that to actually make this color change accessible, we'd need to make it black/white.

Yea, accessibility is probably better handled by users enabling WM-level accessibility features, like using the high contrast GTK theme and checking "use system title bar and borders".

How does cinnamon (the DE in the screenshot, I'm assuming) deal with this with native windows? See attached. There, the frame color distinction is even more subtle. There is a shadow difference, but that's also subtler than CrOS. The title text and window controls seem to be the biggest differentiators. Could we follow suit, changing the appearance of our window controls or the profile switcher or something?

second try..

Deleted: VGurkSQJs68.png 80.6 KB

	VGurkSQJs68.png 80.6 KB View Download

Based on this screenshot, we do the same thing than Cros, i.e light frame and change in window control. If this is sufficient for cros, why not Linux ?

The screenshot in the original comment was for linux with chrome's custom frame. My screenshot is linux with the system native frame (cinnamon desktop environment). The latter is OK but the former is not very distinctive.

ah got it. 
Well, If we can get Chrome custom frame on Linux to react the same way as on Cros, at least we'd get parity. 

Beyond that, I do not think that we can do anything that would drastically improve active/inactive window differentiation without modifying the core UI (tabs/toolbar/buttons) or impacting visual design. 

while we're on the topic, do you think it's time to update the appearance of the window controls? I think they were modeled after a popular style... from 2009. We could always go back to Glen's head.[1]

[1 http://techcrunch.com/2009/08/05/chromes-new-feature-click-the-ui-designer-to-close-the-window/

It would be. To what is the question. These where based off Windows XP I think.

well, the circular ones in the screenshot above (Comment 9) are the default for ubuntu these days, I believe. The theme is called Ambiance.

I have a laptop with my @google.com account and my @chromium.org account in two different Chrome profiles. For some reasons the @chromium.org account uses a black window colour. In this case, there is simply no difference between a focused window and an unfocused window.

Deleted: chrome-focus-issue.png 144 KB

	chrome-focus-issue.png 144 KB View Download

Looks like you're using the GTK native theme. But for that setting (and that GTK theme) I think that focus would have been basically indiscernible even before MD.

You are right. I didn't realise it was a different theme. And you are also right that it is the same on Stable. Thanks for the insights :)

 bug 18668  is about this same topic (preserving WM shadows on custom framed windows) and it was closed as "not possible". I don't know if anything has changed since then, but I also found this comment in desktop_window_tree_host_x11.cc:

    // If the window has system borders, the mask must be set to null (not a
    // rectangle), because several window managers (eg, KDE, XFCE, XMonad) will
    // not put borders on a window with a custom shape.

I think mgiuca@ has some experience with this stuff.

I still think we can at least colorize the (x) if we're going to be copying the appearance of the window controls.

Those colors are sadly coming from the system. If you open up /usr/share/themes/Ambiance/gtk-2.0/apps/chromium.rc, you'll see:

style "chrome-gtk-frame"
{
  ChromeGtkFrame::frame-color = "#3c3b37"
  ChromeGtkFrame::inactive-frame-color = "#3c3b37"

  ChromeGtkFrame::frame-gradient-size = 16
  ChromeGtkFrame::frame-gradient-color = "#5c5b56"

  ChromeGtkFrame::incognito-frame-color = lighter ("#3c3b37")
  ChromeGtkFrame::incognito-inactive-frame-color = lighter ("#3c3b37")

  ChromeGtkFrame::incognito-frame-gradient-size = 16
  ChromeGtkFrame::incognito-frame-gradient-color = "#5c5b56"

  ChromeGtkFrame::scrollbar-trough-color = shade (0.912, @bg_color)
  ChromeGtkFrame::scrollbar-slider-prelight-color = shade (1.04, @bg_color)
  ChromeGtkFrame::scrollbar-slider-normal-color = @bg_color
}

Sadly, Ambiance decided that the active and inactive frame color should be the same. Other themes make different (and sometimes saner) decisions.

yea, but even in chrome classic theme there's not much difference

so to tie this off, perhaps the best we can do is model off the window controls of ambiance, including colorizing the (x) for focused windows. Sound good? It seems like md-ified ambiance window controls should be pretty easy --- circle with -, square, or x.

+ainslie who can create some new svgs for linux window controls (modeled after the native controls in comment 9)?

I imagine it'd be bettes@ 

rpop@, will we also need to do this control-drawing work for Win10 so that we can draw gray title bar instead of default-white behind the tabs and can draw modern window controls for Chrome-Themes folks?

ping?

Sorry I missed #24 at the time. +bsep, will we need to ship our own window controls to move away from the white titlebar on Win10, or can we still use the OS ones?

@bettes, there's a to-do here for you in #23 so assigning to you.

#26: We need to ship custom buttons. I already wrote some here: https://cs.chromium.org/chromium/src/chrome/browser/ui/views/frame/windows_10_caption_button.h

They're very specific to Windows 10 though, and drawn programmatically rather than with svgs. I doubt much can be reused for this.

ping. Poor unloved Linux window controls looking out of date.

Un-cc-ing me from all bugs on my final day.