iOS Mobile - Sign in Modal does not display after tapping Sign In link

• Type: Regression Bug
• Status: Closed
• Resolution: Won't Fix
• Affects Version/s: 7.2.X, Master
• Fix Version/s: None
• Component/s: ~ [Archived] Frontend Infrastructure
• Labels: None

Steps to Reproduce:

1. on iphone or iPad
2. Navigate to localhost:8080
3. Tap on Sign In link

Expected Result:

• Sign in Modal appears and user is able to sign in

Actual Result:

• Sign in link is underlined but no sign in modal displays

Note: workaround failed

• Navigating to http://localhost:8080/en/web/guest/home?p_p_id=com_liferay_login_web_portlet_LoginPortlet&p_p_lifecycle=0&p_p_state=maximized&p_p_mode=view&saveLastPath=false&_com_liferay_login_web_portlet_LoginPortlet_mvcRenderCommandName=%2Flogin%2Flogin
  and inputting sign in data and tapping Sign In button, does not navigate to expected landing page and does not complete sign in for user.
  

Reproduced on:
Tomcat 9.0.17 + MySQL 5.7 + iPhone/iPad + iOS 10 and 9
Portal master GIT ID: ebf44a1f390914a17ba4727a10be3c2e0e8df6d2
Portal 7.2.10 DXP-1