1132429 - Drop in framerate for Youtube Flash videos when opening Firefox context menu and hovering elements

Status: RESOLVED INCOMPLETE

(Core Graveyard :: Plug-ins, defect)

Description

[[SV Manager] Florin Mezei, QA (:FlorinMezei)]

Reproducible with: 
- Firefox 36 Beta 8 - BuildID: 20150209164123
- latest Firefox 37 Aurora (with YouTube Flash Player 1.2) - BuildID: 20150211004833

NOT reproducible on:
- latest Firefox 38 Nightly (with YouTube Flash Player 1.2) - BuildID: 20150211222327

Reproducible on: Windows XP x86

Steps to reproduce:
1. Open Firefox and go to https://www.youtube.com/ and open a video.
2. Make sure Flash is used (use the YouTube Flash Player 1.2 add-on to force flash if needed).
3. While the video is playing right-click outside the video area.
4. Hover the top row with navigation icons while the video is playing.

Expected results:
Hovering elements of the context menu should have no effect on the video framerate.

Actual results:
Hovering elements of the context menu causes a drop in the video framerate (to around 10fps).

The issue occurs in Firefox 33.1.1, but not in Firefox 32.0 (both have the new context menu).

Using mozregression I got a window, but I'm not sure if it's the correct one since it reproduces with the old context menu:
- Last good revision - 2014-05-20 - cb9f34f73ebe
- First bad revision - 2014-05-21 - 9d8d16695f6a
Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=cb9f34f73ebe&tochange=9d8d16695f6a

Note that with the same regression window the Flash context menu hangs Firefox when opened, but this does not show in 36.

Notes:
- Windows 7 experiences some issues as well, but not very visible, and when repeatedly opening context menu, so this is not the issue here.
- I'm not sure if this is an issue with Flash or the context menu, but I suspect it's Flash.
- Similar issues were reported for HTML5 (see bug 1127858).

Comment 1

[Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)]

Flash issue

Comment 2

[u597032]

This website no longer uses flash.