Hi, i had this same issue. One of the plugins caused this but before i’ll get the other plugin to work properly, i added this following code into admin css;
#wpwrap .wpbc_icn::before, [class^=”wpbc_icn_”]::before, [class*=” wpbc_icn_”]::before {
font-family: ‘wpbc-material-icons’!important;
display: inline-block;
}
#wpwrap .bi::before, [class^=”wpbc-bi-“]::before, [class*=” wpbc-bi-“]::before {
display: inline-block;
font-family: wpbc-bootstrap-icons !important;
}
All the admin icons are now visible. The problem itself is not inside a booking calendar plugin but if someone is having this same issue, this might a first aid resolution for this.