Dropdown input breaks after multiple iterations | Is this just me?

A bit of an update:

I visited the notebook with a mobile device using Safari, and the fourth dropdown appears to work there. I also visited with Chrome on a mobile device and the dropdown worked fine, too. So the issue appears to be limited to my desktop and to Chrome.

After rebooting my computer using Chrome, however, I am still hitting the same problem described above: the first three work, the fourth doesn’t.

To troubleshoot further, I borrowed a friend’s computer to view this site with Firefox [Version 60.0.1], but it would not let me connect to the page, saying:

The owner of aaronkyle.static.observableusercontent.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.

and:

aaronkyle.static.observableusercontent.com uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.
The server might not be sending the appropriate intermediate certificates.
An additional root certificate may need to be imported.

Error code: SEC_ERROR_UNKNOWN_ISSUER
Here’s a picture:

… At the same time, the certificate is verified by CloudFlare with a green lock symbol. I haven’t yet managed to get Firefox to connect to see if the error on the fourth dropdown is occurring or not (still not working in Chrome).

Oddly, I get this same error for all Observable pages and can’t get around it.

I would love to hear from anyone about whether there is any known error for different web browsers (or Chrome in particular) whereby one can hit too many repetitions of a n input element on a page? [e.g. DOM select dropdown doesn’t work in Chrome … but this appears to be a bit different, as my dropdowns stop working after the notebook grows too complex…]

Also would be interested if anyone’s had the same trouble with Firefox security issues.

I appreciate any help and guidance!

Sincerely,

Aaron