e.g. https://treeherder.mozilla.org/logviewer.html#?job_id=86490608&repo=try from https://treeherder.mozilla.org/#/jobs?repo=try&revision=a432e5adc397e465aa4884506a5d041ecb8b3d65 - apparently e10s-only, but on all platforms. [Tracking Requested - why for this release]: merge permaorange, closed tree, sadness.

Tracking 55+ based on Comment 0.

It seems that we don't have the separate file-content-process here. That test is for that. I suggest to disable the test. Do you want me to write a patch?

Nah, let's just set the pref that will keep the test working even when it isn't set by default anymore. Note that although https://treeherder.mozilla.org/#/jobs?repo=try&revision=f9722ff493373f0b7918571e6f659ab6871e2518 says this makes the test work, I just blindly copy-pasted that line from another test without actually knowing how pushPrefEnv is supposed to be used or what yield actually means :)

Comment on attachment 8852181 [details] [diff] [review] set the pref Review of attachment 8852181 [details] [diff] [review]: ----------------------------------------------------------------- ::: dom/xhr/tests/browser_blobFromFile.js @@ +2,5 @@ > > add_task(function* test() { > + yield SpecialPowers.pushPrefEnv( > + {set: [["browser.tabs.remote.separateFileUriProcess", true]]} > + ); or enable: dom.file.createInChild

Pushed by philringnalda@gmail.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/61493f82b7a1 set browser.tabs.remote.separateFileUriProcess in browser_blobFromFile.js so it will work even in non-Nightly builds, r=baku