Does anyone have an idea how to contact Solspace support? The email seems to be dead for about a week now.
Try contacting them on the Craft CMS Slack workspace. They have an account on there, it's worked for me in the past!
Use their support form. I quite often get a response after a day or so and they’re very helpful. Here is their Freeform plugin support form https://solspace.com/craft/freeform/support/