[Note]: found while verifying bug 1278287 [Affected versions]: - 47.0.1 (Build ID: 20160623154057) - 48 beta 7 (Build ID: 20160711002726) - latest Dev Edition 49.0a2 - latest Nightly 50.0a1 [Affected platforms]: - Windows 10 64-bit - Ubuntu 16.04 64-bit - Mac OS X 10.11.1 [Steps to reproduce]: 1. Launch Firefox. 2. Open Inspector: Ctrl + Shift + C (for Windows & Ubuntu) or Cmd + Opt + C (for Mac OS X) 3. Select an element from the Markup view and switch to Computed 4. Right click on any property name 5. Select 'Show MDN Docs' option from the context menu 6. Click on 'Visit MDN page' link [Expected result]: The tooltip vanishes. [Actual result]: The tooltip remains visible. [Regression range]: - Also reproducible with 44.0a1 from 2015-10-01 - this looks like a long standing issue [Additional notes]: 1. As a side issue, at step 6, the color of the hyperlink doesn't change when clicked 1.1. reproducible only with Light and Firebug themes 1.2. it doesn't apply for Dark theme on latest Dev Edition and Nightly, but it's reproducible with 48 beta 7; apparently, some bug in this https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=369a5ee3a2880a4a98df3a00bf3db8d8f36b181b&tochange=29662e28a9c93ac67ee0b8ddfb65a9f29bbf73f5 pushlog fixed it with Dark theme. 2. Screen recording: https://goo.gl/CZ9eCV

This has always been the case. So I don't think this is related to bug 1278287. Somewhat related: bug 1146490.