Default Values for Social Media Fields

Hi, I love the automatic social media icons! I was wondering if there was some way to have an option to pre-fill in the first part of a URL for these icons (e.g. https://www.instagram.com/) so that the user only has to add the last part of the URL (e.g. their social media username).

Or more generally- just adding an option to allow for default values within a drop-down custom text field.

Example: A user adds their social media info to the map. Right now, the user just adds their username in one question. The next question the user checks a box next to which social media site their username is referring to.

For context: I currently have an option for them to add their social media URL. The user input rate for this option has been low. Overall, the feedback I’ve received so far from the users has been because A) users don’t know the correct text format for their social media URL, or B) they consider it too much extra work to type it in.
On the other hand, all the users I’ve asked about it have said they like the option of clicking the social media icon and it taking them directly to the linked profile of another user on the map. …so I just thought this might be a good addition/feature to add!

Thanks for your reply in advance!!

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