Telemetry draft

Telemetry

For clients that have "send anonymous usage data" enabled, Firefox Reality sends a "core" ping and an "event" ping to Mozilla's telemetry service. Sending telemetry can be disabled in the app's settings. Builds of Firefox Reality have telemetry enabled by default ("opt-out").

Core ping

Firefox Reality creates and tries to send a "core" ping whenever the app is started or goes to the background. This core ping uses the same format as Firefox for Android and is documented on firefox-source-docs.mozilla.org.

Event ping

In addition to the core ping an event ping for UI telemetry is generated and sent as soon as the app is sent to the background.

Session

Event	category	method	object	value
Start session (App is in the foreground)	action	foreground	app
Stop session (App is in the background)	action	background	app

Browsing

Event	category	method	object	value	extras.
URL entered	action	type_url	search_bar
Search entered	action	type_query	search_bar

Page Load Time Histogram

Event	category	method	object	extras
Histogram for Page Load Times for Foreground Session	histogram	foreground	browser	histogram*

(*) There are 200 extras attached to this event, each a bucket of 100 ms each, with the key as the minimum value in the bucket and the value as the corresponding number of events in the bucket. Anything over 20,000 is put in the last bucket. For example:

{”0":"2"}
{“100”:"3"}
...
{"19900", "4"}

Time spent in Immersive mode

Event	Category	Method	Object	Extra
Immersive mode session	action	click	immersive_mode

URI Count

Event	Category	Method	Object	Extra
The count of the total non-unique http(s) URIs visited in a subsession, including page reloads, after the session has been restored. This does not include background page requests and URIs from embedded pages or private browsing	action	open	browser	total_uri_count
The count of the unique domains visited in a subsession, after the session has been restored. Subdomains under eTLD are aggregated after the first level (i.e. test.example.com and other.example.com are only counted once). This does not include background page requests and domains from embedded pages or private browsing.	action	open	browser	unique_domains_count

Search

Event	Category	Method	Object	Extra
Search bar was used	action	click	search_bar
Search contained URL or search term	??		type_query
Search used voice input	action	click	voice_input
Number of voice queries	action	click	voice_query

Multi-window

Event	Category	Method	Object	Extra
How many too-many-window dialogs happen	action		max_windows_dialog
Usage long press to open new window	action	click	context_menu
Usage of new window tray button	action	click	tray_new_window
How long is a window open for	histogram	foreground	window_lifetime	histogram*
Frequency of window moves	action	click	windows_move_freq
Frequency of window resizes	action	click	windows_resize_freq
Most common window position	??	??	placements_active_time_pct
Curved windows setting use	action	click	curved_mode_active
Time spent in active window position	??	??	left_window_active_time_pct
			front_window_active_time_pct
			right_window_active_time_pct
Concurrent windows per session			one_windows_open_time_pct
			two_windows_open_time_pct
			three_windows_open_time_pct
Average windows per session			window_open_w_mean
Average private windows per session			window_open_private_w_mean
​

(*) There are 200 extras attached to this event, each a bucket of 1000 ms each, with the key as the minimum value in the bucket and the value as the corresponding number of events in the bucket. Anything over 200,000 is put in the last bucket.

Limits

No limits are set to the number of pings we send.