[Tracking Requested - why for this release]: This is a regression in Firefox 47. @ Kyle: could this be a regression from your nsPIDOMWindowInner/Outer changes in bug 1241764? I bisected this regression to this pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=584870f1cbc5d060a57e147ce249f736956e2b62&tochange=b2a3dc4b161fdfac6db78cc5bbfb1f53a383b65a STR: 1. Load an editable Mana page, such as https://mana.mozilla.org/wiki/display/PM/Firefox+Program 2. Click the "Edit" button to edit the page. 3. Click the magnifying class icon to open Mana's Find/Replace toolbar. 4. Enter a search term in the Find field and click the "Next" button. RESULT: Nothing happens. No search matches are found. The following exception is logged to the web console: NS_ERROR_ILLEGAL_VALUE: p.impl/m() batch.js:5939 p/<.find() batch.js:5936 .init/<() batch.js:5923 .execCommand() batch.js:2566 weaveOne/aspect() batch.js:641 .initContextToolbars/k<.click() batch.js:5971 .TextButton/this.render/<() batch.js:3422 d.event.dispatch() batch.js:413 d.event.add/i() batch.js:405

Yeah, this was me.

Comment on attachment 8731895 [details] [diff] [review] Patch Review of attachment 8731895 [details] [diff] [review]: ----------------------------------------------------------------- Is it possible to write a test for this?

Not trivially :/

Comment on attachment 8731895 [details] [diff] [review] Patch Approval Request Comment [Feature/regressing bug #]: bug 1241764 [User impact if declined]: window.find doesn't work in some cases [Describe test coverage new/current, TreeHerder]: There is no test coverage :( [Risks and why]: This is a simple fix, reverting to our pre-bug 1241764 behavior. [String/UUID change made/needed]: N/A

Recent regression tracked.

Comment on attachment 8731895 [details] [diff] [review] Patch regression fix, Aurora47+