STR: 1. Open http://www.w3schools.com/tags/tryit.asp?filename=tryhtml_iframe 2. Hit Ctrl+F and type "w3" ER: "w3"s are highlighted AR: "w" is highlighted And the content process is freezed. If findbar.highlightAll=false, "w3" is highlighted but clicking the next button(or hit F3) - "w3" in the right pane(nested iframe) should be highlighted - causes the content process freezed. Regression range: 13:36.22 INFO: Last good revision: c0c2f6077694008794c06900943654db0143c2b9 13:36.22 INFO: First bad revision: 4988e9ed22f34ffa92723a16b0be9f82f48fe3e9 13:36.22 INFO: Pushlog: https://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=c0c2f6077694008794c06900943654db0143c2b9&tochange=4988e9ed22f34ffa92723a16b0be9f82f48fe3e9

(In reply to atlanto from comment #0) > STR: > 1. Open http://www.w3schools.com/tags/tryit.asp?filename=tryhtml_iframe > 2. Hit Ctrl+F and type "w3" > > ER: > "w3"s are highlighted > > AR: > "w" is highlighted > And the content process is freezed. > > If findbar.highlightAll=false, "w3" is highlighted but clicking the next > button(or hit F3) - "w3" in the right pane(nested iframe) should be > highlighted - causes the content process freezed. I've had this too and I don't need to investigate even to know what's going on here: infinite level of iframes. All I have to do here to remedy this is fix the FinderIterator to only recurse a certain max amount of iframes deep. It'll be hard to find another website that exhibits this behavior, by the way.

http://forums.mozillazine.org/ seems to be affected.

Ugh! Seems I was wrong then :)

I see a consistent hang when I use Find in the eBay watched item list on Windows 7, but not on Linux. The hang happens with E10s off and on.

Also, find-in-page in any Etherpad will cause a hanging process.

Comment on attachment 8791544 [details] Bug 1302011 - if we keep referencing window, currWin will always remain the same, thus never reaching window.top to stop the while-loop. https://reviewboard.mozilla.org/r/78944/#review77524

Pushed by mdeboer@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/6f7790dbfa0f if we keep referencing window, currWin will always remain the same, thus never reaching window.top to stop the while-loop. r=Gijs

Thanks Gijs!

Reproduced the initial hangs/crashes using the STR from the Description and from the duplicate bugs on Nightly 51.0a1 (build ID: 20160911030419) on Windows 10. Verified as fixed using the latest Nightly 52.0a1 (Build ID: 20160926030203) and following the instructions from the description and duplicate bugs on: Windows 10, Ubuntu 16.04 and Mac OS X 10.11.