1705295 - Slow loading of Twitter posts (mobile)

Status: RESOLVED DUPLICATE of bug 1701956

(Core :: JavaScript Engine, defect)

Description

[Asif Youssuff]

Basic information

Steps to Reproduce:

1. Navigate to: https://twitter.com/davidcrawshaw
2. Scroll down

Expected Results:

Fast loading of older Twitter posts.

Actual Results:

Very slow loading of older Twitter posts.

---

More information

Profile URL: https://share.firefox.dev/3uSkDkx

Basic systems configuration:

OS version: Android 11

GPU model: Adreno 540

Number of cores: Octa-core (4x2.35 GHz Kryo & 4x1.9 GHz Kryo)

Amount of memory (RAM): 4GB RAM

Thanks so much for your help.

Comment 1

[Henrik Skupin [:whimboo][⌚️UTC+2]]

This seems to be caused by a script that runs based on FrameRequestCallback. It takes seconds instead of just 17ms to allow a smooth rendering. Could it be that they even do network requests to load the next posts within that script? I can see the same load with Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:89.0) Gecko/20100101 Firefox/89.0 ID:20210411210108.

Olli, is there anything that stands out for you?

Comment 2

[Olli Pettay [:smaug][[e-mail]]]

Those callbacks are really just running lots of JS.

Comment 3

[Iain Ireland [:iain]]

Yet another example of ReactDOM being slow. I think it's safe to call this a duplicate of bug 1701956.