Run the check
Start a drag run and hold the same button without moving for several seconds.
Repeat while moving slowly, then on another surface or connection.
Compare with a second mouse in the same browser session.
Read the result
A release event while the finger remains down is a useful symptom only when repeatable.
Limits and next step
The page cannot tell whether a finger lifted or the device stopped reporting pressure.
Repeat the check after changing one setting or connection. Keep a record of what changed before deciding whether the device needs service.