I see the problem, but I don't know what a good solution would be. Is there some way to trigger a notification only for users with a screen reader or magnifier?

Any updates? How did we handle this issue in other products?

+ lpalmaro who can give you insight about how to solve this issue. Thanks!

Ping! Any guidance on how this could be solved?

lpalmaro@: friendly ping, thanks.

Sorry for the delay on this! I would say that this shouldn't steal focus for the user. So, I believe you should be able to tell when certain assistive technology is being used, see: https://cs.chromium.org/chromium/src/content/browser/accessibility/browser_accessibility_state_impl_win.cc?type=cs&q=Accessibility.WinZoomText&sq=package:chromium&l=71

From there, we can perhaps decide that if a magnifier (e.g. Zoomtext) is on, then we should extend the amount of time that this UI with steps to undo appears on screen instead of the default amount of seconds it appears now. 

Would it be at all possible to make Ctrl Z undo this action, as well? 

Thanks!
It looks like the detailed information on exactly which a11y helper is running isn't exposed, so we can't easily check that. Would simply BrowserAccessibilityState::IsAccessibleBrowser() be sufficient for showing the message longer?
Good idea about Ctrl-Z, but I'm not sure if it's possible - my guess is that the browser itself intercepts that command before the page gets a chance to handle it. If Ctrl-Z indeed turns out to be impossible, could we use some other key combo, or would that be too obscure to be helpful?

Yes, it'd be fine to check BrowserAccessibilityState::IsAccessibleBrowser() as a clue to show the message longer. It will have some false positives, but that should be fine.

I'd like to see if we made the "Thumbnail removed" message into an alert (add role="alert" to the element). I think that might make ZoomText announce it and/or zoom to it, worth a try at least.

Thanks!

Adding role="alert" is trivial and at least shouldn't hurt; I'll get right on that.

Is BrowserAccessibilityState::IsAccessibleBrowser() (or something similar) already exposed to the web page? If not, then it'll require a bit of plumbing.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e8c7004022192affc7a82e1d6c929a2ef54de81b

commit e8c7004022192affc7a82e1d6c929a2ef54de81b
Author: Marc Treib <treib@chromium.org>
Date: Thu Dec 21 09:13:58 2017

Local NTP: Increase 'MV item was removed' timeout in a11y mode

Bug:  779262 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Ib569b7a3dbd96b84e47b53dd6eec0a2230295165
Reviewed-on: https://chromium-review.googlesource.com/831947
Commit-Queue: Marc Treib <treib@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#525652}
[modify] https://crrev.com/e8c7004022192affc7a82e1d6c929a2ef54de81b/chrome/browser/resources/local_ntp/local_ntp.css
[modify] https://crrev.com/e8c7004022192affc7a82e1d6c929a2ef54de81b/chrome/browser/resources/local_ntp/local_ntp.js
[modify] https://crrev.com/e8c7004022192affc7a82e1d6c929a2ef54de81b/chrome/browser/search/local_ntp_source.cc

That should do it :)
+dmazzoni,leberly to verify that this is all good now.

Actually there's one more CL coming in here...

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4b513b8da3fbcfa195414ef5ec9d7af54ac4f083

commit 4b513b8da3fbcfa195414ef5ec9d7af54ac4f083
Author: Marc Treib <treib@chromium.org>
Date: Thu Dec 21 11:40:23 2017

Local NTP: Add role=alert to the 'MV item was removed' notification

This should make the notification more discoverable via a11y tools
such as screen readers or magnifiers.

Bug:  779262 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I5061af8009de5a9c92fdf2aad75edcefad979c45
Reviewed-on: https://chromium-review.googlesource.com/831872
Commit-Queue: Marc Treib <treib@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#525668}
[modify] https://crrev.com/4b513b8da3fbcfa195414ef5ec9d7af54ac4f083/chrome/browser/resources/local_ntp/local_ntp.html
[modify] https://crrev.com/4b513b8da3fbcfa195414ef5ec9d7af54ac4f083/chrome/browser/resources/local_ntp/local_ntp.js

NOW it should be done :)