The minimum sensor type was changed to 1
The maximum sensor type was changed to 42
There is a special sensor allowed -3

Officially, Android does not support sensors outside this range and also a few inside the range.
(For supported sensors, search this Android developer page of the Sensor object.)

SENSORS.LIST {size_nvar,} sensor_array$[]

Gets a list of sensors returned in sensor_array$[].

Any sensors reported from SENSORS.LIST beginning with "Unknown"
is not supported by Android. However, those that are still within the range 1-42 can still be OPENed and READ.
"Unknown" sensors will also try to print their names after "Unknown".
Also (now), this command will remove any duplicate types reported.

If size is given, the array size is returned in size and may be zero.
If size is omitted, and there are no detected sensors, (array size is zero) then there will be a RunTimeError.

SENSORS.OPEN and SENSORS.READ both check (now) if the sensor falls within the allowed range. "Unknown" sensors that are inside this range are also let through. Special sensors e.g -3 are also allowed through.

Unknown Sensors
Here is a list of "Unknown" sensors within range 1-42, which may be of interest.
They are by no means definitive, since each manufacturer can choose their own numbers.
They may or may not work.

Unknown Types

Type	Reported	comment
17	Significant Motion	(samsung, xiaomi)
18	Step Detect	(xiaomi)
19	pedometer	(xiaomi)
22	Tilt detector	(samsung, xiaomi)
27	Orientation	discrete orientation (samsung, xiaomi)
29	Stationary detect	(xiaomi)
30	Motion detect	(xiaomi)
35	Accelerometer-Uncalibrated	(xiaomi)