1097455 - Developer tools network tab with many requests causes UI freeze (multiple seconds)

Status: UNCONFIRMED

(DevTools :: Netmonitor, defect)

Description

[Robin Stocker]

Attachment: test.zip

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:34.0) Gecko/20100101 Firefox/34.0
Build ID: 20141110195804

Steps to reproduce:

1. Extract attached archive to a directory
2. In the directory, start a server to serve the files over HTTP, e.g. using `python -m SimpleHTTPServer`
3. Open Firefox with Developer Tools and the Network tab
4. Load http://localhost:8000/ (or whatever you're serving the files from)


Actual results:

Browser UI freezes/hangs for multiple seconds and is completely unusable.


Expected results:

UI staying usable while page is loading. Chrome has no problem with this, and loads pretty much instantly.

Happens with 35.0a2 as well as 36.0a1 (2014-11-11, with e10s).