Could you please help us with test URL as the URL provided in the screen shot asks for credentials. Is there any other way where we can give a try.

Thanks.!

Here is custom link for test : 
1.open first tab  :
https://www.wabatam.com/testone

2.open second tab : 
https://www.wabatam.com/testtwo , press submit

3.goto first tab : 
press 'submit'

I found out, you don't need to submit on second tab, you can just go back to first tab, and click submit, it will redirect to https://www.wabatam.com/testtwo.

my server (laravel)'s simple code : 
Route::get('testone',function(){
        return "<h3>First Tab</h3><form method='post' action='testonepost'><input type='hidden' name='_token' value=".csrf_token()."><input type='submit'></form>";
});

Route::post('testonepost',function(){
        return redirect()->back();
});

Route::get('testtwo',function(){
        return "<h3>Second Tab</h3><form method='post' action='testtwopost'><input type='hidden' name='_token' value=".csrf_token()."><input type='submit'></form>";
});

Route::post('testtwopost',function(){
        return redirect()->back();
});

Thank you for providing more feedback. Adding requester "ranjitkan@chromium.org" to the cc list and removing "Needs-Feedback" label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

also you can try open one tab, try press submit as many time as you can, it will redirect back to same url, after you open second tab, try to submit again in first tab, it will show different result

Able to reproduce the issue on Windows 10, Ubuntu 14.04 and Mac 10.12.5 using reported version #59.0.3071.86 and latest canary #61.0.3135.0.

Bisect Information:
=====================
Good build: 56.0.2886.0	 Revision(424099)
Bad Build : 56.0.2887.0	 Revision(424315)

Change Log URL: 
https://chromium.googlesource.com/chromium/src/+log/2510d5dc6548c8f4b52d42d1f66f233cd45b7402..1c7f4eba31fca673ed6adbfd2f7e2f04394da590

From the above change log suspecting below change
Review URL: https://codereview.chromium.org/2399643002

estark@ - Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Thanks...!!