User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/17.0 Firefox/17.0 Build ID: 20121031065642 Steps to reproduce: I visited the following page and I moved the cursor to the flash chart: http://es.finance.yahoo.com/echarts?s=AAPL#symbol=aapl;range=2y;compare=;indicator=volume;charttype=area;crosshair=on;ohlcvalues=0;logscale=off;source=undefined; Actual results: When I move the cursor to the chart, the performance degrades significantly. The cursor becomes so slow. Expected results: The performance mustn't be degraded.

I can confirm in Nightly 19.0a1 too. http://hg.mozilla.org/mozilla-central/rev/5bd5bb168eb1 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:19.0) Gecko/19.0 Firefox/19.0 ID:20121101030705 Shockwave Flash File: NPSWF32_11_4_402_287.dll Version: 11.4.402.287 The performance is slightly improved if I set ProtectedMode=0.

Also noted the lag using latest beta Flash 11.5.500.104 on win7 x64 19.0a1 build cset: https://hg.mozilla.org/mozilla-central/rev/71b2ea41dff7 latest hourly. Smooth no log in latest Chrome Dev version with the same flash beta. (I have Chrome's version of Flash disabled)

Is this a regression either in a recent version of Flash or a recent version of Firefox?

First noticeable regression window(m-c) Good: http://hg.mozilla.org/mozilla-central/rev/49afabda6701 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0a1) Gecko/20120115 Firefox/12.0a1 ID:20120115033312 Bad: http://hg.mozilla.org/mozilla-central/rev/823072af2430 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0a1) Gecko/20120115 Firefox/12.0a1 ID:20120115035713 Pushlog: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=49afabda6701&tochange=823072af2430 First noticable regression window(m-i) Good: http://hg.mozilla.org/integration/mozilla-inbound/rev/59cb54c6dfe1 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0a1) Gecko/20120114 Firefox/12.0a1 ID:20120114195007 Bad: http://hg.mozilla.org/integration/mozilla-inbound/rev/5e6e63f3aed8 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0a1) Gecko/20120114 Firefox/12.0a1 ID:20120114201408 Pushlog: http://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=59cb54c6dfe1&tochange=5e6e63f3aed8 Suspected : Bug 598482

bz/roc, who can investigate this?

In local build Last Good : 4616fa6c1dc7 Bug 598482 part 10 First Bad : d7dcde1032ed Bug 598482 part 13 Triggered by: d7dcde1032ed Markus Stange — Bug 598482 part 13 - Flush invalidations via the refresh driver instead of from view update batches. Change the meaning of "refresh disabled" from "no invalidations allowed" to "no synchronous painting allowed". r=roc

Roc or maybe Matt are probably where I'd start.

It's not totally smooth, but very acceptable performance - Win7 Flash 11.8 Something must have improved the situation.