We have barcodes containing the slash character "/", like: 03/07851-a03073 In Koha menu "Circulation > Holds queue" barcodes are now links (in earlier versions they weren't), and the above barcode is shown as 03%2F07851-a03073 This is particularly annoying since this view is often just shown to copy & paste the barcode from the Holds queue list.
Already fixed by bug 36970, it just hasn't made it to 24.05.x yet. *** This bug has been marked as a duplicate of bug 36970 ***