Actually, no Gecko profiler support for Android now...

Copied from bug 1444888: It should be possible to grab a profile snapshot either from the phone's UI or initiated remotely (since using the UI to snapshot can itself mess up your profile or take long enough for the profile to be moot). The size of buffer to be retained and the list of threads to be profiled (and frequency of profile) should be modifiable. e10s profiling should be supported.

Here is an example profile recording on Firefox on Android: https://perfht.ml/2GUsUwG STR: * Enable the new performance recording panel * Open DevTools in Nightly (not in the WebIDE) * Go to the settings by hitting the gear in the top right * Turn on the checkbox "Enable new performance recorder" * Close DevTools * Open up WebIDE * Connect via wifi using the instructions on https://developer.mozilla.org/en-US/docs/Tools/Remote_Debugging/Debugging_Firefox_for_Android_over_Wifi * Go to the new performance tab * Click the record button, then capture. * The profile should load in perf.html interface in a new tab.