Migaku Toolbar Cannot Select Native Language and Target Language

[Anon dc]

The Language Selection section in the Migaku Toolbar is broken for me if I try to use it with Youtube or Netflix.

What I expect to be able to do:
For the "Target" field, I expect to be able to select Japanese from the dropdown menu. For the "Native" field, I expect to be able to select English from the dropdown menu.

The issue:
Most of the time, for the "Native" field I can only select Japanese; no other languages show up.
Sometimes, I cannot select anything for both "Target" and "Native", making Migaku unusable.

I'm not able to reproduce this issue consistently. I'm using Google Chrome with no other Extensions that have access to this website; running Windows 10.

[SteviMigaku]

@anon-dc
What you can select depends on what is provided by the video you are watching.
For example, this video only has Japanese and Portuguese subtitles, so I can only select those.
https://www.youtube.com/watch?v=wZySfwnh5eA&list=PLcm5I05IhDpZ498c_knWUqznpVUUyvgu1&index=5&t=9s
If there is a specific video that has for example English subtitles, but you cant select them, then please link it so we can take a look.