BUG: ResizeObserver loop completed with undelivered notifications.

[ZekeAranyLucas]

Overview

This is a problem that is only visible on the dev server because that's when the overlay pops up. But this is actually a signal of something more sinister in the code. These kinds of problems can cause hangs, unresponsive pages, or just a bunch of jitter. Right now the browser recovers by breaking the loop for us.

Learn more here:

• https://developer.mozilla.org/en-US/docs/Web/API/ResizeObserver
• https://webpack.js.org/configuration/dev-server/#overlay

REPRO

when navigating from "Create Project" or "Feedback" to "My Projects" there is an error overlay

1. run the dev server locally (overlay is only visible there).
2. create at least one project
3. go to "My Projects"
4. go to "Create Project" or "Feedback"
5. go to "My Projects"

RESULTS:

Error overlay as described below.

ERROR
ResizeObserver loop completed with undelivered notifications.
    at handleError (http://localhost:3000/static/js/bundle.js:128757:58)
    at http://localhost:3000/static/js/bundle.js:128776:7

EXPECTED:

no error

NOTE: doesn't repro on refresh of "MyProjects" or navigation from "About" and "FAQ".

Might be something to do with scroll bars

Originally posted by @ZekeAranyLucas in #1508 (comment)

[ZekeAranyLucas]

I did some digging into this, and the key suspects are tooltips or similar overlay components.

[Biuwa]

@ZekeAranyLucas
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2. Blockers(Difficulties or errors encountered):
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[mark-mxwl]

Hi @ZekeAranyLucas, @entrotech, and @Biuwa. I was not able to reproduce the bug in Chrome, Firefox, or Safari. After some digging, I discovered that the error was quite common when upgrading from React Router 5.x to 6. I took a peek at the TDM commit history and, sure enough, there was an upgrade to v6 on Nov. 7, a week before this issue was posted.

Though the TDM codebase doesn't explicitly call the ResizeObserver API anywhere, any number of packages could, including Router. Unless there's an objection, I would recommend that this issue be marked as closed, as changes to packages/dependencies in the ensuing months have, as far as I can tell, sorted this one out.