Copy a field

I have set up a button on a record that when used will copy a file. We use this on a password table and has worked very well. We now want to use the same function in a different table. The problem comes is that the original code is done in javascript that we can no longer use.  Has anyone found a workaround or better way to do this? Code and example below. 

var text CB= URLEncode([Username]);

var text Alert= URLEncode("Activity Details" & " were Copied to the Clipborad");

"<a class='Vibrant Success' style=\"border:0px solid green; background-color:#215732; text-align: center;\"href=" &

"javascript:{" &

"navigator.clipboard.writeText('" & $CB & "').then(function(){" &

"},function(){" &

"});" &

"$.jGrowl('" & $Alert & "',{theme:'jGrowl-green'});" &

"};" &

">Copy Username</a>"

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Joe Rachel
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