What event cannot be copied when triggered (document.execCommand ('copy'))?

The use mechanism of

document.execCommand ("copy") is only available in events that require the user to take the initiative to take action, such as click.
but is there a similar official statement for this" user-initiated event"? Or will each browser provide a compatibility statement?

Jun.21,2022
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-64f5-1b39467-2c173.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b39467-2c173.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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