Can not open element-picking-mode

[Magicool-1]

Prerequisites

• I verified that this is not a filter issue
  • Filter issues MUST be reported at filter issue tracker
• This is not a support issue or a question
  • Support issues and questions are handled at /r/uBlockOrigin
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue
  • Your issue may already be reported.
• I tried to reproduce the issue when...
  • uBlock Origin is the only extension
  • uBlock Origin with default lists/settings
  • using a new, unmodified browser profile
• I am running the latest version of uBlock Origin
• I checked the documentation to understand that the issue I report is not a normal behavior

Description

Not able to open element picker

A specific URL where the issue occurs

www.google.com
www.youtube.com
www.github.com
www.gitlab.com

Steps to Reproduce

1. Right click
   Click on Block Element
   or
2. Click on uBlock icon
   Click on "Enter element picker mode"

Expected behavior:

Element picker should open.

Actual behavior:

1: Right click menu disappears and nothing happens
2: after clicking on element-picking-mode nothing happens

Your environment

• uBlock Origin version: 1.16.10
• Browser Name and version: Chrome 67.0.3396.87 + Firefox 60.0.2
• Operating System and version: Windows 10 Pro 64bit 1803

[uBlock-user]

Enable cosmetic filtering ?

[uBlock-user]

Duplicate of gorhill/uBlock#3212