Can the page listen for browser shutdown events?

after trying onbeforeunload, I don"t seem to be able to do it. Is there anything I can do about it?

Mar.15,2021

my trigger. Both console and pop-up boxes have portal-go to JSRUN to see the effect

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b36b17-2b7af.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b36b17-2b7af.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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