Unable to reproduce the issue on mac 10.11.6 chrome version 52.0.2743.116 and canary - second tab is opened as a new tab

Could you please try the same on a new profile where there are no apps/extensions and update the thread. You can create a new profile from chrome://settings 

Fairly certain this is WAI. I'm removing the Internal>Network label because this has nothing to do with the networking stack, but Security>UX is equally a bad label, since it's not necessarily about the work Enamel is doing.

I'm not aware of a good label for these elements of Chrome UI - perhaps Elly will know if views-ification is touching on this (although I hope not; there is no Views-native UI for this, we use OS-native on Views as well).

+Cc patricialor as last-to-touch, first-to-own

OS: 10.12 Beta 16A313a
Chrome: 55.0.2846.0

I tried:
1) Create a tab, navigate it to https://www.google.com
2) Click the padlock
3) Click the "details" link
4) Click "View certificate"
5) Create a tab with cmd+t, navigate it to http://www.nytimes.com
6) Click a link inside the bounds of the cert viewer in tab 1

The link click worked as expected and mouse-over effects for it were normal.

Cannot reproduce, although I did encounter the far worse  https://crbug.com/643124  in attempting to do so.

patricialor@, is there any way this *could* happen? It seems doubtful to me.

Yep - there were a couple of bugs with the Cocoa certificate viewer and this was one of them. Basically, this is what happens:

1. Open certificate viewer in one tab. An invisible overlay window is also opened underneath the certificate viewer which is set to intercept all mouse events going to the tab below.
2. Open a second tab. The certificate viewer is a window-modal Cocoa sheet, so we pretend it's tab-modal by:
  a) Setting the overlay-window to not intercept mouse events any more, and
  b) Making the certificate viewer invisible and not to accept any mouse events.

The second half of b) is the bug occurring here - the certificate viewer was never set to ignore mouse events. When clicking things under the certificate viewer area, you're actually still clicking on the invisible certificate viewer.

This should be already fixed though, spqchan@ landed https://crrev.com/8fba1d4d58b4e12b1b99df85caf36332bdb4dc07 which mostly fixed this (it kind of just moved the issue to a 1x1 pixel in the bottom-left corner - 0,0 in Cocoa coords) and I was able to change that to just ignore mouse events in https://crrev.com/8f36f7b892825b3117d2b1d2cbd60b05ce6da4ba.

Security>UX component is deprecated in favor of the Team-Security-UX label