How does OpenSeadragon add two magnification buttons zoomInButton?

const viewer = OpenSeadragon({
     zoomInButton: "zoom-in",
});

this button can only be written on the page because it is controlled by id. If you want to write one with the same function, how should I write it?

Apr.10,2022
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-64f5-1b340fe-2bed6.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b340fe-2bed6.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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