I am also looking for the same feature. I have a list of countries and the HubSpot default is single line text (which is a nightmare for any database), so I created a country list as a multiple checkbox list (as some partners work in multiple countries). However, on a form, it is an incredibly long list.
It would be ideal to have this Multiple checkbox list displayed as a dropdown select where people can simply search country by name and select the appropriate ones from the list - something similar to what the HubSpot GUI uses for filters.
Are there any possible fixes/updates/ways around this?
I made a workaround by having the dropdown select as a field and then set up a workflow to append the information to their multiple checkbox property in their profile. So that can then be updated with multiple form submissions from different forms/sources. Not ideal, nor elegant, but functional for now.
Bumping this post - considering the number of uses for multiple select fields, it's surprising this isn't a default feature on a comprehensive CRM tool like Hubspot. For example there are numerous reasons that a form might need to capture multiple country values - do you think anyone wants to scroll through 250+ checkboxes?