FYI, in case you don't read dev.platform. -------- Forwarded Message -------- Subject: Important: Update to latest central before running |mach try| Date: Tue, 26 Feb 2019 15:06:42 -0500 From: Andrew Halberstadt <ahal@mozilla.com> To: dev-platform <dev-platform@lists.mozilla.org>, Firefox Dev <firefox-dev@mozilla.org> If you don't have any |mach try| presets for the syntax selector, feel free to ignore. Otherwise, make sure you update to the latest central before running |mach try| or you might lose your presets. If you see a message like this in your |mach try| output: *warning: unknown section 'syntax', the following presets were not migrated* Then you're too late and it means the presets listed underneath will be lost if you don't manually re-create them. To re-create them: 1. Create ~/.mozbuild/autotry.ini 2. Create a [try] heading and copy + paste the unmigrated presets underneath. For example, the file should look like this: [try] foo = -b o -p all -u mochitest bar = -b d -p none ... 3. Run: mv ~/.mozbuild/try_presets.yml temp.yml 4. Trigger the migration again: mach try --no-push 5. Copy + paste the contents of temp.yml into ~/.mozbuild/try_presets.yml To re-iterate, these steps are *only* necessary if you see the bolded warning above. In short, I recently changed the |mach try| preset format and included an automatic migration script. But due to a bug in the migration, only the first preset in the list was successfully migrated. This bug only affects presets that were saved with try syntax. Unfortunately the associated test for the migration only tested a single preset so didn't detect the bug. The bug is fixed on the latest mozilla-central Very sorry for the inconvenience and let me know if you need help, Andrew