Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100913 Firefox/4.0b6pre ID:20100913041656 [JM]Script timeout dialog appears during loading certain page A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete. Script: https://mijndvn.nl/minify/js?f=/assets/widgets/mootools/javascripts/mootools-1.2.4-core.js,/assets/widgets/mootools/javascripts/mootools-1.2.4.2-more.js,/assets/widgets/mootools/javascripts/moo.rd_v1.3.2.js,/assets/skins/mijndvn/javascripts/site.base.js,/assets/skins/mijndvn/javascripts/site.widgets.js,/assets/skins/mijndvn/javascripts/site.forms.js,/assets/widgets/passwordstrength/javascripts/passwordstrength.js,/assets/widgets/postalcode/javascripts/postalcode.js&1277727801:20 If I set javascript.options.methodjit.content to false , the problem is gone Reproducible: Always Steps to Reproduce: 1. Start Minefield with new profile 2. Open URL ( https://mijndvn.nl/profile/registration/index/ailment/diabetes ) Actual Results: Script timeout dialog appears Expected Results: Page load properly Regression window: Works: http://hg.mozilla.org/mozilla-central/rev/8afc7bd2f495 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100911 Firefox/4.0b6pre ID:20100911204656 Fails: http://hg.mozilla.org/mozilla-central/rev/421427ca9809 Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100911 Firefox/4.0b6pre ID:20100911215458 Pushlog: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=8afc7bd2f495&tochange=421427ca9809