Failing tests: devtools/client/debugger/new/test/mochitest/browser_dbg-breaking.js devtools/client/debugger/new/test/mochitest/browser_dbg-breakpoints-reloading.js devtools/client/debugger/new/test/mochitest/browser_dbg-chrome-create.js devtools/client/debugger/new/test/mochitest/browser_dbg-chrome-debugging.js The refactoring is currently only on: https://github.com/zer0/gecko/tree/event-emitter-1381542 We need to address the test failures before land this patch in m-c.

Here the original try build with the failures: https://treeherder.mozilla.org/#/jobs?repo=try&revision=bba13e27a2371fa8aad68b9b227534b31829cb0d Those failures are most likely due the breaking change in how the `EventEmitter` emits event. Previously, the first argument was the event type: myEmitter.on("custom-event", (eventType, message) => { ... }); Now the first argument is the message: myEmitter.on("custom-event", (message) => { ... }); In the majority of the scenario the `eventType` is ignored by our code, so we should just remove it from the function's signature. For more details and edge cases, see: https://github.com/devtools-html/snippets-for-removing-the-sdk/#events

This appears to have been fixed by one of the other refactoring bugs. Closing this as a duplicate