I am trying to set the RelatedTo field of activity to search in a custom object. In classic we can simply use URL hacking & custom button. But in lightning this solution is not viable. I tried few ideas to set default value but to no avail. By default Related To has Accounts...Also I know there is an Idea Pending with salesforce.
So if anyone know ANY way to set "Related TO" field on Activity please let me know. Is visualforce page/ lightning component to replicate the whole Activity section ..the only option?
Thanks for your time:)