[ANSWERED] Warning: "IntersectionObserver.observe(target)"


Windows 7 SP1
Atom V1.19.3
TYPE: Console warning


The following warning message appears on the console at start-up of Atom:

target element is not a descendant of root.
TreeView @ <embedded>:107279

I hope that someone can direct me in the right direction on where to look to identify the root problem.

This warning appears when starting Atom or restarting by ctrl-shft-f5. This message was not there in Atom V1.18. I doubt if it was there on Atom V1.19.0.

What I have tried already without a positive result:

  • Executing atom --safe from the command prompt.
  • Uninstalled Atom V1.19.2 and then installed V1.19.3.
    The .atom directory was not deleted.
  • Clear styles.less and init.coffee
  • Update all dependancies.
  • Disable all community driven packages.

Steps that had an influence:

  1. Remove all project folders from the tree-view.
  2. Close Atom.
  3. Open Atom.
  4. The tree-view is closed as there are no folders/files to display.
  5. Checking the console - there are no messages.
  6. Open the tree-view by ctrl-\, opens the empty pane. No message.
  7. Add a folder to the tree.
  8. Close Atom.
  9. Open Atom.
  10. tree-view is open and console reports a problem.

With ‘preserve log’ set, a more detailed list is available:

<embedded>:107279 IntersectionObserver.observe(target): target element is not a descendant of root.
TreeView @ <embedded>:107279
getTreeViewInstance @ <embedded>:61169
deserialize @ <embedded>:69769
deserialize @ <embedded>:20001
(anonymous) @ <embedded>:28727
module.exports.Pane.deserialize @ <embedded>:28726
deserialize @ <embedded>:20001
deserialize @ <embedded>:28163
deserialize @ <embedded>:30224
deserialize @ <embedded>:25980
(anonymous) @ <embedded>:1501
Navigated to file:///C:/Users/Dan/AppData/Local/atom/app-1.19.3/resources/app/static/index.html

Following the HTML file:

<!DOCTYPE html>
  <meta http-equiv="Content-Security-Policy" content="default-src * atom://*; img-src blob: data: * atom://*; script-src 'self'; style-src 'self' 'unsafe-inline'; media-src blob: data: mediastream: * atom://*;">
  <script src="index.js"></script>
<body tabindex="-1">


Any suggestions on where to look next?
Thank you.


It started happening with the last Electron upgrade


Thank you for the reply.

I am confused. The bug report you linked to?.. is it not related to viewing / rendering? On face value I see nothing wrong with the representation of the texts and information. There is only the message to show there is some issue somewhere.

How / where does the link relate to the topic?
(no emotional reply implied with my response)


The link is the specific code change where this warning started. The warning started because of the Electron upgrade that was a part of that PR. The PR also contains the editor rendering rewrite that was made in Atom 1.19.

If you want to dig further and learn more about the warning the place to start your search would be why Google Chrome added this warning. It was later also removed in Chrome 58: https://bugs.chromium.org/p/chromium/issues/detail?id=693166#c6


okay… thank you, it is more clear now why you linked to that post.
I cannot help but wonder if it can be linked to latency with loading the relevant coding,
It is as if the mechanism that report the error should be delayed until Atom is loaded properly.

The delay period I see for reporting that packages cannot update because of no internet connection seems to be okay.

I guess that if it is a Chrome related issue, it will not be fixed until the Electron base is updated again.

Thanks for your efforts.


Yeah sorry about the short reply in my first post. If I remember correctly this warning was harmless and since it will go away in a future version we did not address it.

Yeah, the warning will be there until we update Electron.