Customixing the buttons below event description (Quick Info)

I would like to change the buttons that appear below the quick info event text.


Or grafik

Specifically, I would like to do that:

A short search allows me to find these icons:

$ grep -oE 'icon_[a-z_]*[^}]+content:"."}' dhtmlxscheduler.css | sort | uniq
icon_alert:before{content:""}
icon_arrow_down:before{content:""}
icon_arrow_up:before{content:""}
icon_calendar:before{content:""}
icon_cancel:before{content:""}
icon_check:before{content:""}
icon_clock:before{content:""}
icon_close:before{content:""}
icon_details:before{content:""}
icon_dots_h:before{content:""}
icon_dots_v:before{content:""}
icon_drag:before{content:""}
icon_drag_horizontal:before{content:""}
icon_drag_vertical:before{content:""}
icon_edit:before{content:""}
icon_form:before{content:""}
icon_iclose:before{content:""}
icon_loading:before{content:""}
icon_menu:before{content:""}
icon_menu_down:before{content:""}
icon_menu_right:before{content:""}
icon_ok:before{content:""}
icon_plus:before{content:""}
icon_save:before{content:""}
icon_small:before{content:""}
icon_sort_asc:before{content:""}
icon_sort_desc:before{content:""}

I wonder: How can I change the items provided there? What is the customization function?

I found this:

I am not sure, yet, how I can attach a custom link/action to the links.

This seems to be described here:

So, I will try this out and see. This solves my use-case. Thank you for the documentation!

I made it really nice with SVG icons, too!

.dhx_menu_icon.icon_subscribe {
mask: url('/img/icons/subscribe.svg');
mask-size: 100%;
}

Credits:
https://codepen.io/noahblon/post/coloring-svgs-in-css-background-images