Unable to click continue button after completing puzzles

[77vjdplu1N2h]

Exact URL of where the bug happened

After finishing a puzzle, the continue (to next puzzle) button stopped working. It was working yesterday.

Steps to reproduce the bug

1. Go to https://lichess.org/training/mix.
2. Complete a puzzle.
3. Click continue.

I've tried reloading the page or opening the page in a new tab. I'm presented with the same puzzle and the issue still happens. I also tried restarting Firefox.

What did you expect to happen?

Continue to next puzzle.

What happened instead?

Nothing happens. The page seems to be stuck.

Operating system

MacOS Sonoma 14.4

Browser and version (or alternate access method)

Firefox 150.0.1 (aarch64)

Additional information

I will attach a video in a moment.

[77vjdplu1N2h]

The video file was too large to attach so I uploaded it to imgur.com instead:

https://imgur.com/a/cRs3gr9